There is a problem with a batch of Amstrad PVR2's that results in sound-skipping or glitches, together with associate picture break-up. I have noticed postings in the Sky User forums about this but apparently the widespread extent of this problem or how to get it resolved has not been identified here. By following this link you will find detailed information about this problem, and what simple steps can be taken to get to it resolved with a free call out from BSkyB and a free PVR3 replacement.

SKY + sound is skipping on recorded programmes - Page 87 - Digital Spy Forums

Good luck, and looking forward to seeing you on the other side for this particular issue.