I see the error "Unsupported Mode" with my Sony Media Center PC to Sony XBR2, though my PS3 works great connected to the LCD.
I use optical out for sound. The error goes away when i reboot the PC. Have not been able to figure it out.

--Avi

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Samsung 65" 8500, xbox 360
Sunfire AV7702
Marantz AV7704
Sony UBP-X1000ES
M80s, VP180, QS8s, EP350