Got a Premiere a couple of weeks ago to replace a dead Series 3. Have had many problematic recordings with pixilation, macro blocking and stuttering. Tonight I tried to watch the Sharks playoff opener on Comcast Sports Net and nearly had an aneurysm because the picture was unwatchably bad. Two calls to Comcast and nothing helped. Every so often the picture would clear up, and then turn bad again without warning. It was strangely periodic, and it didn't matter which channel I was tuned to. Finally, in desperation I changed the channel to the analog Comcast Sports. I'd forgotten how awful SD looks on my 60 inch HDTV, though. I flipped to the other tuner and changed to the HD Comcast Sports Net. Voila! PERFECT picture! It finally dawned on me: the SD channel consumes only a fraction of the bandwidth of the HD channel. Could it be that the Premiere just couldn't handle it? I flipped back to the SD station and tuned to HBO HD. Back to Comcast Sports HD, and the pixilation was back. Just as bad as before. Switched the other tuner back to SD and Comcast Sports HD immediately cleared up. Have been watching it for half an hour now and not a dropped frame. So is this a bug, or is the Premiere just unable to stream two high bandwidth HD channels to disk at one time? Or could my two year old eSATA, TiVo certified expansion drive be the problem? It should have way more bandwidth than necessary for two HD recordings and another HD playback stream. Anyone know? Too late for me to contact TiVo support tonight so I thought I'd ask here.