I have a customer with a theater that recently (this year) started showing this message, and the screen flashes the message, when the theater is turned on.

Theater consists of Yamaha RX-A3030, DTV HR23, Apple TV, an Ethereal HDBaseT extender, and a Sim2 D80.

To make the problem more irritating, it doesn't always happen. And sometimes switching sources and going back to DTV fixes the problem. I've not seen the problem happen on ATV. And sometimes if I power the theater down, wait for the projector to cool down and turn it back on, it works fine.

Firmware is up to date on the Yamaha. I've tried everything Brent has suggested, except tell the customer buy a new projector. I tried an SDI extender, but the only coax run to the projector was that 25awg mini coax with the stranded core. I don't know if my termination was high enough quality to work. It checked good when I tested the wire, but I don't know if it really was. I called sim2, and they were the usual help of "that is a very reliable projector" (every projector I've sent to them happens to always return NPF, $500 bill for bulb and new firmware). Sim2 even hinted at the Yamaha could be the problem instead of the projector.

I don't want to tell the customer buy a new projector and the problem still not be solved.

Oh, I forgot to mention, I tried switching DTV back to component and calling it done, but the picture had lines in it, similar to a ground loop, but a lot more lines and they didn't move.