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Frequently Asked Questions

The FAQ pages contain answers to frequently asked questions and solutions for many problems.

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Got a problem or question? Are you in need of help? Then visit our forum and the experts there will do their best to help you.

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Bug Reports

Found a bug? You can report it on our forum. The experts there will help diagnose the problem and forward the information to the appropriate developers so that the problem can be fixed.

It is extremely important that you report problems. Don't assume that other people have the same problems as you have. Our experience is that many people don't report bugs or wait very long. We can only fix problems if we know they exist!

It is also important to realize that a lot problems are caused by external factors, such as drivers or third party software. So it is not something we can fix by a change in our software. But we can help you find the cause and provide a solution.

Problem solving tips

  • Apply fixes and reset settings with the Codec Tweak Tool that is included in the K-Lite Codec Pack:
    Codec Tweak Tool > Fixes
    Codec Tweak Tool > Settings > Reset
  • Update to the latest version of the codec pack. A re-install can often fix damage done by third party software.
  • Game crashes when it should display an intro or cutscene video? Modern games often require Media Foundation codecs from Microsoft. These are not always installed in certain European and Korean versions of Windows. If your Windows does not include Windows Media Player, then you need to install Media Feature Pack from Microsoft to get the required codecs.
  • If you get a BSoD, then you need to update your graphics driver (or revert to an older version of it).

Tips for Windows Media Player

Fix playback issues with MP4 or MKV files. For example broken audio, video, or no subtitles.

Solutions:

  1. On Windows 10 you can install some additional Media Foundation codecs for WMP. This will allow you to play some additional video formats, such as HEVC and VP9. However, this may not be enough for solve all problems.
  2. Rename your file from so it has extension .video instead of .mp4/.mkv
    This forces WMP to use the DirectShow codecs from K-Lite instead of the Media Foundation codecs from Windows. The codecs from K-Lite work better than the ones from Windows.
  3. Codec Tweak Tool > Media Foundation > disable for .mkv or .mp4
    This will also force WMP to use DirectShow codecs. Warning: This will break playback of such files in applications that require Media Foundation. Games and web browsers often need Media Foundation, so we strongly advice against using this solution. Please read the help file in the Codec Tweak Tool.
  4. Use Media Player Classic (MPC-HC) player from K-Lite instead of WMP. This player is superior to WMP.

Playback of HDR video

These are videos with a wider color range than normal.

First of all you need to use a player that supports HDR video. We recommend using Media Player Classic (MPC-HC) player that is included with from K-Lite. WMP does not support HDR.

You also need to use a video renderer that supports HDR. The K-Lite Codec Pack contains two renderers that are compatible with HDR: madVR and MPC Video Renderer. You can choose the renderer that MPC-HC uses during installation of the codec pack, or here after install:
MPC-HC options > Playback > Output > Video Renderer

MadVR has the ability to passthrough HDR to your TV/Monitor. It is also capable of tonemapping the colors for display on normal SDR screens. It use a high quality algorithm for this. MadVR works best with powerful GPUs. MPC Video Renderer only supports basic tonemapping. But it works better with lower-end GPUs.

Playback of UltraHD HDR videos requires modern hardware, with a graphics card (GPU) that supports hardware accelered decoding of 10-bit HEVC video.

If you are using Windows 8.1 or 10 then we recommend using the D3D11VA hardware acceleration option in the codec pack for best performance with madVR. On Windows 7 you need to use DXVA2 Copy-Back. If this gives performance issues, then use DXVA2 Native instead. CUVID is not compatible with HDR.

Solving audio problems

Audio isn't working in MPC-HC

Change the audio renderer:
MPC-HC options > Playback > Output

If volume is very low:
Codec Tweak Tool > Fixes > Reset Windows Audio Mixer volume

Solutions for stuttering, crackling, drop outs, and lip sync issues:

  1. First check CPU usage during playback. Press Ctrl+Shift+Esc to open Windows Task Manager. If CPU usage is close to 100% then your computer might not be powerful enough to play high resolution videos. Visit our forum for advice.
  2. Disable fast startup in Windows 10: Windows Control Panel > Power Options > "Choose what the power buttons do" > uncheck "Turn on fast startup"
  3. Windows Control Panel > Sound > Speakers > Properties > Advanced > disable the two "Exclusive mode" options
  4. Windows Control Panel > Sound > Speakers > Properties > Enhancements > Disable all sound effects
  5. On laptops: Windows Control Panel > Power Options > select "High performance" power plan. If this works, then increasing the value of "Minimum processor state" in the other power plans may also solve it.
  6. Update your sound driver. Many computers have Realtek audio chip: latest Realtek driver (use generic one). You can also use the generic "High Definition Audio Driver" from Microsoft.
  7. Use Latency Monitor to check if you have any driver installed that cause high DPC latency. Such drivers should be replaced with a newer (or older) version.
  8. If you have overclocked your CPU, then reset to stock speed and voltage settings, and test if that makes any difference.
  9. If you have an Intel CPU, the use InSpectre tool to disable the Meltdown/Spectre protections. These have a negative impact on performance and increase latency. It does not matter much for security since most modern web browsers already provide protection against these processor flaws.
  10. If you are running virtual machines using Hyper-V, then closing the VMs might solve audio stuttering.
  11. Antivirus software can sometimes also cause DPC latency, for example when they monitor network activity. Try removing it and just use the built-in scanner from Windows 10.
  12. Check if a BIOS update is available for your motherboard.