i have not had this problem before. i installed a theater on friday for a customer and when i programmed the remote I was testing everything out i noticed when i tried to go from the dvd source which is a blu ray back to a hd cable station the cable image or sound will not come back. im using the denon 791, a samsung bdp1500, optoma hd2200, motorola comcast hd box. I've used this set up before except with last years denon model, and i see that it upconverts to 1080p, is that my problem? The projector keeps searching for a signal and the cable box keeps flashing dui? I know at my house on my lg lcd my box says that for a second when i switch from a non hd channel to a hd channel. please help i need to whats causing this. thank you

And I thought I had long run-on sentences.

Are you using HDMI or component with digital audio?

Try using component for the cablebox. One less headache to deal with.

Second that.

thanks

Sounds like the cable box isn't re-negotiating correctly. Do you have other HDMI sources or just the two?

The cable box is saying "dVI", not "DUI". :)

just the two for now