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Playback issues

Q:I can't play a certain video file
A:

Read the rest of the FAQ. There may be a topic related to the file type that you are trying to play. Here is a list of general tips:

  • Click on the shortcut called "Reset to recommended settings" in the start menu.
  • Load the file in the MediaInfo tool. That can usually give you some useful information about the contents of the file.
  • Test the file in Media Player Classic. For two reasons:
    1) It is better able to play certain files than other players.
    2) It shows more helpful error messages.

If all fails, then try the VideoLAN player. This player doesn't use DirectShow filters to play files, but it's own plugins. It should be able to play almost anything.

Q:I am unable to play any files on Windows Vista even though I have all the proper codecs installed
A:

First use the Codec Tweak Tool to check for any possible problems. Enable these fixes:

  1. Detect and remove broken ACM/VFW codecs
  2. Detect and remove broken DirectShow filters
  3. Re-register base DirectShow filters

If the above does not help, then the problem might be related to the User Account Control (UAC) functionality of Windows Vista/7/8. Disabling UAC can often cause weird problems. Uninstall the pack. Re-enable UAC and then re-install the pack.

Q:I am not able to play AVI files
A:

If you are not able to play any AVI files at all, then the AVI source filter of Windows is probably broken.

You can fix it using:
Codec Tweak Tool -> Fixes -> Re-register base DirectShow filters

Or manually from an administrator command prompt with this command:
regsvr32 quartz.dll

If the problem only occurs with some AVI files, then the file is damaged/incomplete/fake or you are missing a codec. The MediaInfo tool can tell you what kind of video format the file contains.

If the file shows you a video message about a missing codec that you need to download, then you got a fake file. Do NOT download the codec it points to. It is likely to contain a virus or other malware.

Q:I have trouble playing certain MPEG files
A:

Use the MediaInfo tool to get details about the file.

If the file contains MPEG-1 video, then try enabling MPEG-1 in ffdshow or LAV video decoder. By default Microsoft's own MPEG-1 decoder is used.

If the video looks all messed up or is completely black, and the file contains MPEG-2 video, and also the Chroma subsampling has value 4:2:2, then you should use a different MPEG-2 decoder. A good choice is ffdshow.

If the file still fails to play, then try setting LAV Splitter as the preferred splitter with the Codec Tweak Tool.

Q:I can't play AVI files anymore after using WinAVI Video Converter
A:

WinAVI sometimes breaks the AVI source filter of Windows.

You can fix it using:
Codec Tweak Tool -> Fixes -> Re-register base DirectShow filters

Or manually from an administrator command prompt with this command:
regsvr32 quartz.dll

Q:I have trouble playing incomplete AVI files in Media Player Classic
A:

Install the Gabest AVI splitter. That is better capable of handling partially downloaded AVI files.

Q:I can't play .avi files that contain H.264 video
A:

Early versions of CoreAVC have trouble decoding H.264 video when the video is stored in the AVI container. Updating CoreAVC to the latest version should solve this problem.

Another solution for playing these files is to enable H.264 decoding in ffdshow. Go to ffdshow video decoder configuration. At the Codecs page, set H.264 to libavcodec.

If you are using Media Player Classic Homecinema, then you should also disable the internal DXVA H.264 decoder. You can do that in: MPC Options -> Internal Filters.

Q:I can't play .avi files downloaded from video.google.com
A:

Select the Gabest AVI splitter during installation of the codec pack. That splitter is better able to handle those files than the default AVI source filter that is part of Windows.

Q:AVI files containing H.264 video play upside down in BS.Player and WMP
A:

This problem should only occur in combination with old versions of CoreAVC. So make sure you are using the latest version. Another solution for playing these files correctly is to enable H.264 decoding in ffdshow. Go to ffdshow video decoder configuration. At the 'codecs' page, set H.264 to 'libavcodec'.

Q:Two audio tracks are being played simultaneously
A:

This means that you are using a player that doesn't contain a stream switcher. If you play a file that contains multiple audio/video/subtitle streams, then your player is trying to play them all at once instead of just one of them.

Solutions:

  • Use a player with a built-in stream switcher. For example Media Player Classic.
  • Use a source filter that contains a built-in stream switcher. For example LAV Splitter or Haali Media Splitter contain that functionality. The K-Lite Codec Pack uses these splitters by default for most formats. If you also want to use one of these two splitters for .avi files, then you need to manually select it during installation of the codec pack. You can also change the preferred AVI splitter at any time with the Codec Tweak Tool.
Q:When playing movies with AC3 sound the video often skips
A:

ReClock might solve your problem.

Q:The CPU usage is very high during video playback, any tips on how I can lower it?
A:

Video playback can require a lot of processing power, certainly when the video has a high resolution (720p/1080p/1080i). Some video formats, such as H.264, are very complex to decode.

Some tips to lower the CPU usage are:

  • Use a hardware accelerated decoder for H.264 video. For example the internal DXVA decoder in Media Player Classic. You can enable it in: Options -> Internal Filters.
    A hardware accelerated decoder offloads the video decoding to your graphics card (GPU), significantly reducing the workload of your CPU. Your graphics card needs to support this functionality, but almost all cards manufactured in the past few years support it.
    If you use a different player than Media Player Classic then you could use the hardware acceleration options of ffdshow or LAV Video instead.
  • Disable the "Allow animation when buffering" option in the DirectVobSub subtitle filter. That lowers CPU usage a bit. Animated subtitles (such as found in some anime videos) may not display correctly with this option disabled, but such subtitles are rare. The same option can also be found in Media Player Classic for its internal subtitle renderer.
  • Disable subtitles.
  • Disable resizing, and also any other post-processing filters that you might have enabled in ffdshow.
  • If you have forced ffdshow to always output RGB32, then allow it output in the YV12 and YUY2 colorspaces.
  • Use the Overlay Mixer renderer. This video renderer uses a bit less CPU cycles than other renderers. Recommended only on Windows XP.
  • Close other programs that are also running on your computer that use a lot of CPU cycles. For example P2P programs.
  • For H.264 video, you could enable the skip deblocking option in ffdshow. You can find that option on the Codecs page in ffdshow video decoder configuration. It is located near the bottom of the window when you select H.264. Be aware that enabling this option leads to reduced video quality. In some cases it has only a minimal impact on quality, but sometimes it can lead to significant blocking and other decoding artifacts. We do not recommend enabling it.
Q:The video stutters and does not play smoothly
A:

This is sometimes caused by buggy graphics drivers. Make sure that you are using recent drivers. You can download the latest drivers on the website of the manufacturer of your graphics card or chip. That is in most cases AMD/ATI, NVIDIA, or Intel.

If you don't know what kind of graphics card you have, then the Codec Tweak Tool can help you out.
Codec Tweak Tool -> Generate Log
The system information section of the log contains details about your graphics card and current driver.

A common cause for stuttering are performance issues. If your computer is too slow to decode the video it will result in suttering and frame drops. Read the topic with tips on how to lower the CPU usage.

Another common cause for playback to have some occasional stuttering is a difference in framerate of the video and the refreshrate of your monitor. Ideally the refreshrate is a multiple of the framerate. Media Player Classic has special options that allow automatic adjustment of the refreshrate. See MPC Options -> Playback -> Fullscreen.

Media Player Classic allows you to choose which video renderer is used. Changing the renderer may sometimes help improve playback smoothness. See MPC Options -> Playback -> Output.
Recommended renderers for Vista/7 are: madVR (on high-end computers), Haali, EVR Custom Presenter, EVR.
Recommended renderer for XP are: madVR (on high-end computers), Haali, Overlay Mixer, VMR-7 (windowed), VMR-9 (renderless).

If the problem only occurs with certain AVI files, then read this FAQ entry.

If the problem only occurs with certain MOV files, then read this FAQ entry and this FAQ entry.

If the problem only occurs in MPC with certain WMV or M2TS files, then read this FAQ entry and this FAQ entry.

If you are using DXVA or CUVID hardware accelerated decoding, then try disabling that and using pure software decoding. That may sometimes help, certainly if you make use of PixelShaders in Media Player Classic. A high GPU load can give problems, just like a high CPU load can give problems.

Video playback is very sensitive to timing. Certain monitoring programs that run in the background can cause trouble if they make excessive use of timers. Examples of tools that you shold avoid having running during video playback are: CPU-Z, GPU-Z, Process Explorer, Speedfan, and similar programs.

Q:The video is not synchronized with the audio
A:

A typical cause for this problem is high CPU usage. The video can't be decoded fast enough to keep up with the audio. Read the topic with tips on how to lower the CPU usage.

Q:The video plays very slow and parts are skipped. It is like I am watching a slide show.
A:

A typical cause for this problem is high CPU usage. The video can't be decoded fast enough and as a result frames get dropped. Read the topic with tips on how to lower the CPU usage.

Q:The video stutters a lot when I play it fullscreen
A:

This can be a result of certain graphics card settings. Try changing the following settings in your graphics card control panel:

- Set FSAA to 'Let the application decide'
- Disable anisotopic filtering (AF)
- Disable antialiasing

Q:The audio volume is really low
A:

This is a common problem that is usually caused by playing 5.1 channel audio on stereo speakers. Buggy or badly configured audio drivers may then output just two audio channels to your speakers. This means that the center channel, which usually contains the dialogs, is not outputted to your speakers.

Take the following steps to properly configure your speakers:

  1. Use the Codec Tweak Tool to configure your speaker settings. This will make sure that the audio decoders that are included in the pack downmix (or upmix) the audio to the appropriate number of audio channels.
    Note: These speakers settings are the same as those displayed during the installation of the codec pack.
  2. Go to the Sound settings in the Windows Control Panel and also check if the number of speakers is configured properly there.
Q:The volume of voices is very low compared to the background sounds and other sound effects
A:

See the above topic for instructions on how to properly configure your speaker setup.

Even when the number of speakers is configured correctly, the volume of the voices can still be too low compared to the sound effects. This is simply how the movie studios have mixed the sound track.

Here are some way to boost the volume of the center channel that contains the voices:

  • When using ffdshow as audio decoder:
    ffdshow audio decoder configuration -> Volume -> enable Volume and Normalize
  • When using ffdshow as audio decoder:
    ffdshow audio decoder configuration -> Mixer -> increase Center slider to above 100%
  • When using AC3Filter as audio decoder:
    AC3Filter options -> Mixer -> Voice -> change value to for example 10
Q:The volume of voices is too high compared to the other sounds
A:

Disable the "[AC3Filter] Boost voice/dialog volume" tweak during installation of the codec pack. This only applies in the situation where AC3Filter is installed.

It is also possible to manually disable this tweak. Go to AC3Filter options. On the 'Mixer' tab, set the 'Voice' slider to value 0.

Q:Vorbis audio in MP4 container does not play
A:

Use LAV Splitter or Haali MP4 splitter instead of Gabest MP4 splitter. You can configure your preferred source filters with the Codec Tweak Tool.

Q:MP3 files play too fast in Windows Media Player
A:

Go to AC3Filter settings. On the System tab, disable PCM.

Q:Video plays too fast in Windows Media Player
A:

Go to AC3Filter settings. On the System tab, disable PCM.

Q:How can I play AVI files from Blizzard Games?
A:

Videos belonging to games from Blizzard contain DivX video, but with a different FourCC, namely "BLZ0".

To play such videos you need to use ffdshow for decoding DivX video. The regular DivX decoder won't work (unless you manually change the FourCC).

Go to ffdshow video decoder configuration. On the Codecs page, set DivX 4/5/6 and Generic MPEG-4 to libavcodec.

Q:Some .mov and .3g2 files play without sound or video
A:

Solutions for playing such problematic files:

  1. Use the Codec Tweak Tool to change the preferred splitter for .mov files. We recommend using LAV Splitter.
  2. Use Media Player Classic. This player is able to use the QuickTime framework for playing .mov and .3g2 files.
    To enable the use of the QuickTime framework do this:
    Media Player Classic options -> Formats -> scroll down to "QuickTime file" -> Change "DirectShow" to "QuickTime" on the right side
  3. Install MediaLooks QT Source filter. This is a special DirectShow filter that uses the QuickTime framework for decoding. This filter is compatible with several DirectShow players, including Windows Media Player and Windows Media Center. This filter is NOT needed if you use Media Player Classic, because that is already able to directly use the QuickTime framework. See above.
  4. Use VLC Player.

Important: solutions 2 and 3 require that QuickTime or QT Lite is installed.

Q:How can I make 6 channel Windows Media audio play properly on stereo speakers?
A:

WMVHD files, typically created for playback on the XBOX360, can contain a 5.1 audio stream. If you play such a file on a computer that only has two speakers then you will only hear the sound from two of the six channels. This causes for example the voices (center channel) to be almost unhearable.

The solution is to downmix the 5.1 channels into 2 channels. There are two ways to do this. You can either use AC3Filter or ffdshow.

In ffdshow audio decoder configuration, go to the 'Codecs' page. Scroll down to the bottom of the list and set 'Uncompressed' to 'All supported'. Now go to the 'Mixer' page and set the speakers to '2/0 Stereo'. Also enable the checkbox in front of 'Mixer' to activate the mixer filter.

In AC3Filter options, go to the 'System' tab and enable 'PCM'. Configure the output setting to stereo speakers.

Q:Seeking within an AVI file has a delay of a few seconds in Winamp
A:

Disable Gabest AVI splitter using the Codec Tweak Tool. Or select the Microsoft AVI splitter during installation of the codec pack.

Q:Seeking within an AVI file is not smooth
A:

This problem only occurs for some people. Symptom is that the video freezes or goes black for a short while.

Solution is to select Microsoft as the preferred splitter for AVI files in the Codec Tweak Tool.

Q:When using Vista Media Center the video freezes for a few seconds every few minutes
A:

Updating your graphics driver to a recent version should fix this problem.

Q:I can't play WMV files.
A:

You need to install the Windows Media Format Runtimes. These are also included with Windows Media Player.

Windows XP/2003/Vista:
Windows Media Format Runtimes v11
(Do NOT use this on Windows 7. It will not work!)

Windows 98/ME/2000:
Windows Media Format runtimes v9

If you remove WMP on Windows 7, then the windows media codecs are also removed. You need re-install WMP in order to get them back.

If you are using a special N or K edition of Windows 7, then you need to install this to get the Windows Media codecs: Media Format Feature Pack for Windows 7

Q:I can't open AVI files with WMV3 video in editing applications such as VirtualDub
A:

You need to install WMV9VCM.

Q:I get some message about acquiring a license when I play certain media files
A:

That means that the file is DRM protected. DRM is a copyright protection method. You generally need to get (read: buy) a license to be able to play the file. Our advice: shift+delete.

Q:I am having trouble playing .mkv files that contain "720p" or "1080p" or "x264" in their filename
A:

This are high resolution videos in the H.264 format. Playing such files requires a lot of processing power. High CPU usage can cause various problems. Video will stutter, frames will be dropped, and audio goes out of sync.

Read the FAQ entry tips on how to lower the CPU usage.

Q:I am unable to play .vob files in Windows Media Player
A:

This is caused by a bug in Windows Media Player. Simply renaming your .vob file to .mpg will make it playable in WMP.

Media Player Classic has no problems with playing .vob files.

Q:Audio stutters on Windows Vista
A:

Open the Control Panel and click on the Sound applet. Select your output device in the list that appears. It is usually called "Speakers". Right-click on the device and in the context menu click on Properties. Click on the Enhancements TAB. Enable "Disable all enhancements".

Q:Some MOV files stutter during playback
A:

Cause #1:

Stuttering with HD QuickTime files, which contain H.264 video, is usually caused by performance issues. See this FAQ entry for general tips on how to improve playback performance.

Media Player Classic may have been configured to use the QuickTime framework for playback of MOV files. That framework has much worse performance compared to DirectShow. A quick way to boost performance of MOV playback is to rename your .mov files to .hdmov. Then the DirectShow framework will be used.

If you prefer that MPC should always use the DirectShow framework, then change this setting:
MPC Options -> Player -> Formats -> scroll down to QuickTime file and at the right side change QuickTime to DirectShow.

The MPC-HC version included in the pack already uses DirectShow by default for MOV playback, so the changes above should normally not be needed.

Cause #2:

Stuttering can happen with .mov files that contain SVQ3 video, if the file is parsed by Haali Media Splitter. Decoded frames are then sometimes displayed in the wrong order. The solution is to set LAV Splitter as the preferred splitter for .mov files. You can do this with the Codec Tweak Tool.

Q:There is a long loading delay when you open an .mkv file
A:

Matroska files have the ability to link several related files together. The delay is caused by Haali Media Splitter looking for linked files. This can result in a significant delay if there are many .mkv files in the same directory.

The solution is to disallow Haali Media Splitter to search for linked files.

Haali Media Splitter options -> Input -> set "Try to open linked files" to No.

Q:How do I play M2TS files that have been ripped from a Bluray disc?
A:

You must set the preferred source filter (a.k.a. splitter) for M2TS files to LAV Splitter or Gabest splitter. You can configure your preferred source filters with the Codec Tweak Tool.

Be aware that the content protection of the Blu-ray disc must be removed before you can play the files. You can do that with a tool such as AnyDVD HD.

Q:AVI files with Xvid or DivX video stutter in Windows Media Player or Media Center on Windows 7
A:

Windows 7 contains its own decoder for MPEG-4 video (DivX, Xvid, etc). Some people are having problems with that decoder, such as stuttering and bad visual quality.

Windows Media Player and Windows Media Center will default to using Microsofts own decoders. Changing the preferred decoders is possible with a special tweak tool called Win7DSFilterTweaker that is included in the codec pack.

Tweaks that you should try (in this order):

  1. Change preferred DIVX/XVID/MP4V decoder to ffdshow or LAV Video.
  2. Disable Mpeg4s Decoder DMO and Mpeg43 Decoder DMO on the Tweaks page.
  3. Change preferred MP3 decoder to ffdshow.
Q:MP4 files play without video in Winamp on Windows 7
A:

Use Win7DSFilterTweaker to change the preferred H.264 video decoder. The recommended setting is USE MERIT. Also enable H.264 in either LAV or ffdshow video decoder settings.

Q:.tp files recorded with Hauppauge software are out-of-sync during playback
A:

Disable "MPEG-TS (Haali)" with the Codec Tweak Tool.

Q:How do I play WAV files that contains DTS audio?
A:

The recommended solution is to rename the file from .wav to .dts. Then it will be parsed by the AC3File source filter, which will properly recognize the contents as DTS audio. AC3File is included in the Full/Mega/64bit packs.

An alternative solution is to enable decoding of both DTS and Uncompressed audio in ffdshow audio decoder.

Q:M2TS files that contain VC-1 video play with just a black screen in Windows Media Player on Windows 7
A:

The standard Microsoft codecs used by WMP on Windows 7 do not support VC-1 video inside M2TS files.

Use the Win7DSFilterTweaker tool to disable Media Foundation.

Q:Some DVD rips created by AXXO give a black screen during playback
A:

This happens because those videos have a width that is not a multiple of 8. That causes compatibility problems with some video renderers.

Assuming that you are using ffdshow for decoding the video, there is a workaround to properly play such video files. In ffdshow video decoder configuration, you should enable the "Resize & Aspect" filter. Select the setting called "Expand to next multiple of: 16".

Q:My player freezes during file opening when S/PDIF is enabled in ffdshow
A:

ffdshow audio decoder configuration -> Output -> uncheck "Connect as PCM first"

Q:MKV files with DTS-MA audio give audio stutters/pops/crackles during playback
A:

This is a known problem with Haali Media Splitter. It is related to the way the file was created. That problem has been fixed in MkvToolnix, so re-muxing the file can help.

The recommended solution is to fix the file. This can be done relatively easy:

  1. Download MKVToolNix.
  2. Open Mkvmerge Gui and select Header Editor from the File menu.
  3. Open your mkv file
  4. Under default duration for the audio track(s), click on Add Element and enter the value 10666666 (for DTS-MA) or 833333 (for TrueHD).

Another solution is to use a different source filter for .mkv files. You can change the preferred source filter with the Codec Tweak Tool, assuming you have a secondary splitter installed.

Q:I have problems playing certain RealMedia files
A:

Update to the latest version of the codec pack. That uses the LAV Filters for playback of RealMedia Files. That works pretty good. Previously the Gabest RealMedia Splitter and ffdshow were used. That combination worked less good and could give problems such as: stuttering video, audio problems, and thumbnail problems.

If you want to use an externally installed version of MPC in combination with the LAV Filters, then you should disable its internal RealMedia source filter and decoders. The MPC included in the codec pack is configured properly automatically.

If LAV Filters do not give you satisfactory results, then you could try VLC player instead.

Q:Seeking in RealMedia files sometimes results in a loss of audio or audio distortion
A:

RMVB files that contain AAC audio may give problems after seeking when using ffdshow or LAV Audio decoder. Seeking again may sometimes restore sound.

Such RMVB files work better when using one of the following AAC decoders:

  • AC3Filter (included in Mega and 64bit pack)
  • Monogram AAC decoder (included in Full and Mega pack)
  • Microsoft DTV-DVD Audio decoder. This decoder is included with Windows 7. To use it simply disable AAC in both ffdshow and LAV Audio decoders (or uncheck AAC during installation of the pack).
Q:Karaoke files on a VCD (.dat) with dual mono MP2 audio play as stereo
A:

Disable MP2 in ffdshow audio decoder. The the standard Microsoft MPEG audio decoder is used. That will properly recognize the audio stream as dual mono and it will play the first mono channel by default.

Q:MP4 files that contain video with a variable frame rate play at the wrong speed
A:

Use the Codec Tweak Tool to change the preferred splitter. LAV and Gabest work better in this case than Haali.

Q:Files with DTS audio give stuttering playback
A:

ffdshow audio decoder -> Decoder settings -> uncheck "Enable jitter correction"

Q:I am having SPDIF problems with ffdshow
A:

One setting in ffdshow that may help is "Connect as PCM". Try with that setting disabled.

If that doesn't help, then you could try using AC3Filter instead of ffdshow. AC3Filter is included in the Mega (and 64-bit) versions of the codec pack. You can choose during installation for which formats you want to use it.

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