TV is a new Vizio E600i-B3. STB is an IPC1100 attached to TV with an HDMI cable (Verizon supplied). TV is set to "Normal" image. STB is set to 1080i, 16:9, SD Override = OFF. When the TV was turned on the first time with the STB, the HD output signal was 1080i as reported by the TV using the "Info" button on the Verizon Remote. I powered the TV and STB completely off (unplugged from wall) to move the equipment and plugged everything back in. Now the STB is transmitting everything in 480p regardless of the transmitting station selected (High Def or Standard).
I have swapped the HDMI cables, tried component connections, powered everything down to reset the TV according to Vizio's directions and rebooted the STB several times. Nothing changes the output.
Any suggestions?