I have a similar issue with my Panasonic TH-50PZ85U. The Watch TV command only turns the TV on every other time. If it is the time that it didn't turn on, and I again select Watch TV, it still doesn't turn on. But if I turn everything off and then select Watch TV, the TV does turn on. Turn it all off and this time the TV does not come on upon selecting Watch TV. In other words, it is exactly every other time.

The Help button corrects the issue by turning the TV on at that moment, but it doesn't correct the issue long term. The issue remains.

I've gone through the Troubleshoot functions in the PC software, tried changing the delay times, etc.

I followed Sucubus' instructions on how to find HDAVI on my TV, but the path mentioned doesn't exist, and I can't find any mention of HDAVI.