As the subject says. It's not all the time, You pause a program and it just unpauses after about 20 minutes or so. The other thing it does is skip to the current point when you're watching a program that has been paused and then you can't rewind.
Firstly I'd like to welcome you to the forums and can I say that I'm sorry to hear that you're finding that sometimes when you pause live that it unpauses after a while.
I'd like to ask if when this happens, do you notice that there are other recordings taking place, as this may explain a little - especially if there are a few things being recorded.
I've tried to locate your account in order to run some testing on the TiVo® but I was unable to do so with the details you have on your forum account, so I'll send you a private message in order to ask some further questions. Please look to the top left of this page where you'll see a red envelope icon. Click on this and you'll see my message.