I have a TiVo HD with an M cable card. I tried to install a tuner adapter and found that (after Cablevision authorized it), I could no longer control the TiVo. It's stuck on LiveTV on one channel. When I press any remote button, the orange LED on the TiVo lights, but nothing happens. No TiVo Central, no channel change, no Guide. I disconnected the tuning adapter (coax and USB) and unplugged the TiVo for several minutes. After restarting (without the tuning adapter connected) the TiVo works OK for several minutes, then goes back to being stuck in LiveTV.

Any ideas?