Same thing happened to me the other day. Black screen for all live tv and my recordings. Reboot fixed it. Hadn't happened since.
not using hdmi.....I've seen this on my Premieres as well. Instead of reboot, my solution was: unplug HDMI, turn TV off, replug HDMI, turn TV back on. Hope that helps.
Happened again, iPad app just spins ...not using hdmi.....
(I got tivo unstuck once by using the ipad app, but I haven't tried that trick on this bug)
This issue has now happened to me twice. I have been one of the few Premiere owners without a lot to b*tch about, but this one is starting to piss me off. I don't even use netflix, or anything else on my tivo, beyond recording shows. I use the SD menus. This is a reliability issue with the most basic functionality of the tivo.This is supposed to be fixed in 14.9.