Panasonic SA-AK520 not responding, powers on

I have a Panasonic SA-AKX520 that does power on, but doesn't respond to ANY button, as it is frozen, can't do ANYTHING! does the "cold start" as I have the service manual and did that, but still... dpoesn't say HELLO, like it used to, NOT responding to ANYthing, could it be a power issue? I checked power supply and it does have the 30v or whatever, I do know about electronics, and computers, but not that much about electronics, just reading schematics, soldering, basic stuff... measuring.. canI upload a video here showing what it does? can anyone HELP?? it is a voltage regulator?