Should easily clear up turning tv off 2 mins then turn it on prior to turning on device being attached when switching devices to clear.tv memory of said device.
Look into HDMI port with flashlight to see bent pins. Hold up gently and hold then diwnwards when signal is poor to see if HDMI to motherboard connector is loose from misuse. Any signs of change at all??
Just considering you bumped or forced too much and loose connector now for example.
People. Get cheap surge protectors for your expensive equipment, tvs especially and computer towers. Electricky spikes are common especially foreign