I have Comcast cable service and just got the Comcast Scientific Atlanta Explorer 8000 HD cable box/DVR unit. I've recorded several HD programs and have noticed both audio and video problems. Mostly audio drop-outs and digital artifacts with some video drop-outs as well. Quite frankly, I'm not convinced that this records in true high definition at all. The recordings do not look as "crisp" as the live broadcasts. Anyone else experiencing these problems with this unit? Does anyone know how I can tell which firmware the unit is using? Can I get updates from Scientific Atlanta or Comcast; or do they update automatically?