ok so.. i have this problem every so often having a 5.1 system the sound is tricking changing from one satellite to another without hearing from the others, 1 min later the pc completly freezes

how can i pin-point the problem?

any help please!!!

Have you checked in your device manager to see if any of the devices are showing an error? (the yellow exclamation point symbol)
Have you tried updating or reinstalling your audio drivers?

Maybe you could try checking the Event Viewer to see if it shows any error codes around the time of the crash.