THD Pillar Box (panel mode) Issue

When watching certain (not all) SD channels in "panel" mode (as TiVo calls it) I get the grey side bars. However, on the left side, between the show image and the grey side bar is a black side bar (about an inch wide). Happens on FX, TNT, CNBC, MSNBC (among others), but not on CNN, Spike, Bravo (among others).

I tried tuning the problem channels on my TiVo Series 2, and my Comcast/Moto HD DVR, and the issue only exists on the THD.

While I don't always watch SD in panel mode, it's annoying to have the extra black bar, and is also a screen burn in issue.

Anybody else have this issue? Anybody know how to resolve (TiVo support couldn't help)?

 

The reason the TiVo HD has grey sidebars by default, is this is less damaging (from a screen burn in perspective) than black bars, so I don't want black sidebars.

Regarding overscan, why would the same channels viewed on my TiVo Series 2 & Comcast/Moto HD DVR not have the black side bar?

 

Is this extra black side bar what others are experiencing as well? Wondering if I have a bad box or not.

 

My area has ADS so all channels received on the THD are digital. Very strange--and annoying, especially since my TiVo Series 2 and Comcast/Moto HD DVR don't have the issue (and the Series 2 only receives analog)