If you notice this only during TNT NBA broadcasts, I will guess the issues are with the broadcast, and not the Tivo.
I think I may have noticed the issue myself. I think I may have even noticed the same issue on NBA TV channel, but I think the same studios and "broadcast chain" are being utilized, by and large.
If it happened on other stations, I might worry. I'm on Comcast cable btw.
Tivo HD Lifetime 1TB int, 1TB ext Dead for now.
Tivo 540040 400 GB Lifetime Storage only.
Tivo S2DT 750 GB msd Storage only.
Toshiba sdh400 r.i.p.