Originally Posted by cranny
George what do you mean you updated the firmware and it messed up the HDMI?
After I updated the firmware and removed the flash drive, I turned the TV back on and, on "HDMI" source, got a black screen with the "no signal" display to the lower left. The HDMI had worked just fine right up to the point I upgraded the firmware.
When I set the TV to "Tuner", with direct input from the cable, the set worked fine. If I used "Tuner", but instead set it to channel 3 and used the RF output from the cable box, everything was also fine, including all the cable box functionality. So the basic operation of the TV and cable box was OK; only HDMI was affected.
I suspect this was a "handshake" problem, as the cable box was also confused, flashing "dul" on its display every 5 seconds or so (unless I turned off the TV). My understanding is that, with HDMI, the cable box and TV communicate with each other to work something out, and were failing to do so with the new firmware. This was indicated by the "dul" message, which is apparently the way that "dvi" has to be represented on a 7-segment display. So my guess is that the cable box thought it was supposed to be speaking DVI instead of HDMI (very similar but not similar enough?).