Not all players can decode 5.1 from that. Kick the supplier of the MKV to answer what's up and how to play.
Bob
I got these pc 5.1 speakers. I went home, plugged them in and evergthing was ok. I oopened a song and sound was coming from all speakers. Not surround type of sound meaning that it was like normal sounds from the front speakers and secondary sounds from the rear ones but everything from everywhere. When I opened (and open) 5.1 enabled movies everything was and is ok. Now today I noticed that while playing an mkv movie I was getting all sound from the center speaker and humming from everything else. Testing shows that they work properly. Help?

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