That's it. It's because the tuner the mini chose was already on the channel, so it had the buffer.Strange thing is it sometimes works with the Enter/Last button. Two programs are both buffering 30 mins. It doesn't always work. My guess is that I got lucky and one (or maybe both?) of these channels is being "watched" on the main TiVo.
This is my main issue with the mini, not being able to cycle through a available tuners. As I mentioned in another thread, if this screws up thr main tivo user, then add a setting to designate which tuners the minis have access to. So the main Tivo can lock say 3 or 4 and the other 2 or 3 would be the ones available to the mini to cycle through.
Thus would make the mini much more enjoyable.