Series2 80-Hour DT Audio Issues

[fess]

Hi all I need some help here. I got this unit for my wife for Christmas. I have it hooked up to basic cable only. I set it up last night and let it load the programing. All seemed fine until I was showing my wife how the dual tuners work. All of a sudden when I switched to the second tuner the audio would start to cut in and out. It continued to do it even when I switched channels. I flipped back to the other tuner and the audio was perfect. I continued to flip back and forth between the two tuners, changing channels along the way. No matter what I tried the audio would always be choppy on the second tuner. There isn't any distortion and the picture quality is fine on both tuners. At first I though maybe it was a weak signal but wouldn't that cause the same problem on both tuners? Anyway the cable running to the the Tivo is only split once with a two way splitter if it matters.

So what am I looking at here? Anyone else with similar issues? Did I get a dud??

Thanks for your time.

Fess