I have a Series3 HD TiVo with software version 11.Ok-01-2-652, and Optimum digital cable with two S-cards. Don't think it matters but I also have a 1TB WD external drive. It's worked on Optimum ok for about a year, but it was a bear getting it setup. They first brought an M-card but couldn't get it to work. They then brought two S-cards which seemed to work, but after they left I found I was only getting the very basic channels. The next day a tech spent three hours at my place getting the two S-cards working: on the phone with Optimum, would tell them to change a setting, have to reboot my TiVo, didn't work, change another setting, reboot etc. over & over. Finally got them both working ok. Don't know if any of that matters, but the problem I'm having is that occasionally I or my TiVo will tune to a channel and it will be black. No 'Searching for signal' messages, just no picture. Sometimes its only one tuner (i.e. card) sometimes its both of them simultaneously. Its never a premium channel as I don't subscribe to any. It's usually an HD channel but sometimes it will happen on an SD one too. The only thing I can do is just keep changing the channel up or down and it usually finally appears, though not always. I used to try rebooting and ejecting & reinserting both cablecards but that doesn't seem to work any better than just changing channels and takes much longer. This problem used to occur only occasionally, but in the last few months it seems to be happening more and more. Signal strength is between 90-100 on both cards whenever I check it. There's only my TiVo and one other Optimum cablebox with only one splitter in the basement installed by Optimum, so I don't see how it could be a signal strength issue. I'm afraid it's probably an Optimum cablecard issue because: My dad's TV that's connected to their cablebox never does this. I previously had this exact same TiVo on FiOS with their M-card and it was easy to setup and worked rock solid, no problems whatsoever for nearly three years. Is there anything I can try? I'm really hesitant to call Optimum because I know they're just not sympathetic to cablecard problems and their solution will just be to tell me to use their DVRs instead!