I have that problem on my new TiVo HD, however my cable company is RCN. So, what constitutes too hot a signal in terms of the data I can read on my tivo's Diagnostics screen? Channels that are causing intermittent pixelization problems for me have signal strengths in the range of 87-93 with occasional peaks up to 100. The signal to noise ratio (SNR) display for those channels sits around 35-36 dB. Might those values be considered too high? If so, what range of values should I be trying to hit when I start adding attenuation? Any advice on this would be greatly appreciated. Thanks.