Audio AND video cut out, then come back on E75-E1

I have a Vizio E75-E1. I typically run my source from my PC, but have double checked this problem from the other input sources and it remains. I have performed all the standard quick fix attempts listed on Vizio’s website… power cycle, multiple source check, factory default reset, software update. The audio AND video both cut out at the same time, stay off for about 5-10 seconds, then come back. Lately, the problem has gotten worse, with the TV sometimes actually shutting off. Also, just lately, it has started to affect the video card on my PC, with the PC readjusting how many screens it senses (it is configured to recognize 3 screens at once), and auto adjusting to run two screens (with the TV absent). I don’t know if this is a power supply problem (like the 120V in), a board problem (main board?), or some sort of other problem I don’t know of.