We've experienced the same problem since day one with our HD DirecTiVo. From what I've read here, the brief "black outs" and sound pops are unique (and rather ubiquitous) to the system. I'm not saying everyone has them, but I've seen multiple reports of these issues here. Like you, we only have these problems on HD recordings, from sat or OTA. I think the general consensus has been to chalk it up to early days in the HD DVR field. If anyone knows something different, please correct me.