Advertisements You are correct. All the tuning and decoding is done in the TiVo just like all the other channels. TA just provides a channel map to TiVo and handles the SDV protocol to the head end. It could very well be coming down the pipe hosed up. Natgeo was like that for a while... Discovery HD too... TWC fixed those here. Discovery HD is still wonky sometimes. One thing you can do is tune the offending SDV channel and then go into TA Diags. There you can also find signal strength and SNR. TA will actually give you dBmV measurement of signal strength. I found that in Raleigh... the SDV carriers are HOT HOT HOT by about 3-4 dB compared to the non-SDV's.