thanks for the time and detail of your post. my moms toshiba sd-h400 wouldnt boot past "powering up" so she had brought it to me because i knew that was an hdd issue having known my own dvr. after replacing the hdd, then came the "no signal detected on: cable in" video issue within the tivo gui, which was unexpected. It was troubleshooting a couple weeks to try to figure out a combo that would work to no avail. (ex. coax only, composite only, mix, etc.) i got soo frustrasted after a couple google searches, i put it up for sell and sent back the tivo wifi adapter i bought for it. well, within the next week, i was prepared again for a challenge so i plugged it up and whoila...i have a cable picture. lol. now i stopped the potential sell of it and had to get those accessories back like the tivo wifi adapter, etc. by the time i got them back, i had been through a power outage, guide info had run out, and now im back to the "no signal detected on: cable in" video issue. lol. then i started the google searches again and came across a lot of people with this issue and this post was very helpful and also another as far as how to connect up tivo to cable box on another site. i hadnt noticed the live tv yellow button not being on anymore (but recall seeing it light up the room) and the rf in nub was a little loose but after tightening from outside..still nothing. so i opened the tivo casing(while unplugged and always ground yourself) and got my butterknife to undo those pesky metal clamps at the top of the rf casing. it looks like the metal part that touches the rf in is in place but i still tried to force it closer in with a screwdriver. well, i then plugged it back up and have live tv on the front of tivo and picture on the screen! that is too crazy. i, like others, was getting cable after turning off tivo, through the tivo rf out so that gave me hope. also, when plugging coax from wall to tivo and coax from tivo out to tv after pulling it out of the closet..i thought i had another chance to get it restored. i currently have it working through my cable box. i would suggest have coax from wall to cable box in, composite cable from cable box out to tivo composite in, and coax out from tivo to tv.. it is switching channels on the cable box with the ir cable. also, when going through guided setup, it said "found video signal" on composite so that made me happy. im a moxi person but i take from my mom in that she likes dvrs i suppose. we will see if it stays working when i send the tivo back to moms though...lol. it should be ok but its a hassle when power is interrupted for any reason. update: my mom got the tivo and although live tv didn't work after she 1st plugged it up, 1 powercycle of the box and its good to go. i hope power isnt interrupted anytime soon.