Not to necro-post, but I just saw this thread, and I had similar issues a few months back with my Mini as well. Coincidentally, it was happening around the same times my digital cable box was also acting totally wonky (freezes, channels blacking out, very slow response to remote commands), and I thought it was very strange that both devices would act up around the exact same times. Both devices got so bad for several hours on multiple nights, it was maddening. Now that I think of it, I’m gonna throw out a wild guess and say it was probably my ISP/cable provider having some kind of issues with the area network. I have no idea what it could have been, but that’s the only thing my cable box and iPad have in common. Of course my ***** provider knew nothing if any issues in the area and wanted to send a technician out to investigate, which I promptly refused. Mysteriously after a couple of weekends of that frustration, the problem cleared itself up, which strongly suggests to me it was them and not me.