Was finishing up a job, testing, programming the remote, and the BluRay was acting strange and giving an error message of U73.

Here is the equipment: Panasonic DMP-BD60, Denon AVR1910,Dish VIP722K sat receiver, Samsung LED 42" not sure the exact model. All are switched through the AVR. HDMI connected and one HDMI to the display.

Here is what happens: The sat plays fine, no issues. The BD will load the disc and you can see the numbers moving on the display until you switch the input on the AVR, then it kinda stutters and shows the message U73 on the BD display. If you switch the AVR input back to sat, the sat plays fine, and the BD display reverts to the word PLAY, but doesn't seem to be playing. I switched the input on the AVR from dvd to hdp thinking that could be the problem but it didn't change anything. At no time does any picture from the BD show on the display, not even a menu or logo.

I had to be somewhere else the next day, was waiting on a couple of volume controls to come in, so I re-scheduled after making sure they had sat, and I need to get back to do an in-depth troubleshooting. I will bypass the AVR with component to see if I get a picture, try to do a firmware update etc. The thing that is throwing me the most is the player running until I switch the input on the AVR. I could understand if the error message showed up immediately, but it you switch the input and turn off/on the player, the message goes away (until you switch the input again). Also, I didn't have a BD disc to test it, and neither did the customer(they are new to this) and only had a SD disc to run.

I am just looking for any insight before I go back that will possibly make the troubleshooting faster or more productive. Anyone hear of a similar problem before?

Thanks in advance.