Yes. I do have the same problem. I had to hard roboot or unplug the HDMI cable from Nextbox 3.0 and plug it back to get the signal and pictures.
It all started from January 11th , when they changed to new Navigator guide. I have been calling Rogers tech support and no solutions so far. They say its a know issue and waiting for the patch. So far nothing happend. Very frustrated. Maybe I will disconnect the TV subscription.