I booted the Xbox One in safe mode (480p) and was able to get a signal that way and could even boost the output to 720p in settings but when I tried to set it to 1080p I get bounced back to the original resolution. So there's something about 1080p video from Xbox One that this receiver doesn't like.
In the meantime I've got the Xbox One going directly into the TV and if I can't fix it will run optical audio from the Xbox One to the receiver so I can get surround but I'd much prefer it if it would just run HDMI through the receiver the way it's supposed to.
Anyone have any ideas? This is driving me nuts!