Problem with computer speakers

[L1ght]

Hi, I'm having some problems with getting my 5.1speakers to play the sounds through all speakers while watching video files. When listening to music or any other application I can get the sound through all five speakers. I'm using my onboard soundcard which is realtek HD audio, and I've set everyhting to 5.1. I've downloaded the latest codec from CCC and using windows media classic, but still having this problem.

Anyone got any ideas? Thanks

 

[L1ght]

no worries i solved the problem. K-lite seemed to fix everything

update: I just tried to play an mkv file and i seem to be having some lip sync issues, although the sound is comming through all speakers now, the video also doesn't seem to be running properly. I then tried to watch a blu-ray and there was just a massive hissing noise. Anyone had this problem before? Would this be a windows problem or audio driver problem?