WM5 Media Player Sound Problem

[Guest RB_]

when i watch mp4's i've loaded on to my card they play fine but most of the time when i pause the video and unpause it the sound wont come back on but the picture plays fine.

also when watching a mp4 it will sometimes stop and go back to the begining of the clip and i have to press play again.

i've turned off all power saving option so the screen dosent go off but i still have the same problem.

does anyone have any ideas?