Unplug all HDMI and other connections to the set. Remove the power cords to all afflicted machines for about 10 minutes and then hook up only what you need to test.
The SLIM PS3 is the worst offender here and has had me carry other HDMI cables with me to test that out. LONG HDMI cables also are trouble.
I have a Samsung UN55C7000 TV with a PS3 hooked up to it via HDMI. All of a sudden now I am seeing this message when I turn on both:
Mode Not Supported
The resolution is not supported on this TV. Please change the resolution.
This comes up after working for the 4 years of having both setup with no such issue and no setting changes!!! I have reset the PS3 video settings to use HDMI and a 55" inch screen, and even reset the TV settings to default, and this message comes up for a bit, then blinks back to the PS3 menu, then blinks again to the Mode not supported message, back and forth. TV has no software upgrades to install either.
So I'm at a loss about what to do next. Any thoughts or help here?