Advertisements I recently moved and I have run into an odd issue when trying to use my Tivo Series 3 and cable modem at the same time. Without the series 3 hooked to the cable line, the cable modem syncs perfectly and has a great signal. About 3 minutes after I hook up the series 3 to the same line, the cable modem drops signal. This 3 minute delay leads me to believe its not just a signal strength issue. Both of these were working perfect at a previous location. Curious if anyone has seen something like this before. I doubt Comcast is going to be willing to be much help as both devices are customer owned.