I had the same issue that got progressively worse, started out by freezing, then moved to pixielating, then would do some random high pitched buzzing through the speakers. Only way to temporarily reset was to turn the truck off. All the fixes mentioned above will not work. How do I know? Three new radios later (yes that is correct THREE radios) I tried all the easy fixes first.
Hopefully you have warranty. The first radio that was replaced I waited months for, supposedly backordered. Interestingly enough it was also defective but with different symptoms. The second radio, had the same issues as the factory radio. Finally on my third one, technically fourth including the factory radio, and I have been trouble free for over a year....fingers crossed.
One peice of advise. As usual when I would bring the truck in they couldn't replicate the issue, as it was random. I took a video with my phone next time it happened and went back and showed the service director. He had the tech come out and watch and that was proof enough they needed for a warranty claim.
A trip to the dealer is in your cards....