Sometimes no sound when playing some videos

Question

Some .mkv videos I try to play using Media Player Classic won't play audio. Those same files will play audio when played with VLC. DVD's also play without audio. This leads me to believe there could be a hardware issue between the motherboard and the audio card. However, I do not know the googlefu terms to research this possibility myself. Does anyone have any input to offer?

Answer 1

It's much, much more likely that the videos in question have audio encoded in a format MPC doesn't recognize but VLC does... If some files play fine on both, then it's not a hardware problem.

Find two files, one with audio on both players, one with VLC only. Open each in VLC and look at the "Stream Information" window for the audio stream codec... There is where the difference exists.

Answer 2

This is surely a codec problem.

Both MPC and VLC were originally developed by Gabest. However, MPC is now a community project, and its currently active fork is Media Player Classic Home Cinema.

VLC comes with its own codecs, while MPC uses the DirectShow codecs that are installed in the computer (same as used by Windows Media Player). Apparently you are lacking some codecs.

To install a very complete codecs-suite, download and install the K-Lite Codec Pack.
Uninstall first MPC, since K-Lite installs Media Player Classic Home Cinema.

Answer 3

I had the same problem, noticed it with the official Unreal UDK tutorial videos in MP4 format. About half of the time videos were muted. After one or a couple of reloads the audio would play eventually. Close and restart of the player was not necessary for this. Used mpc-hc64.exe K-lite codec pack on Windows8.1.

After installing "Media Player Codec Pack 4.3.4" (link: http://www.techspot.com/downloads/downloadnow/5333/?evp=81b4f3b1d0ba02fa9b917f8eaad468ee&file=1 ) all videos played well, with just the same media player.

Please notice that the installer asks you on the final page to install third party software that looks like spyware to me. Just "do not accept" if you don't want it and click install, it will only install the codecs then. Reboot is not necessary.