Marantz SR7007 amp issue

I've had this receiver for about 7 years and generally worked very well.  Just prior to year 4 (so covered under warranty) the unit stopped producing sound.  Typically when turning on the unit, there's one "click" the it goes off of standby, and then ~5 seconds later, there's another 'click' presumably the amplifier kicking in as that's when sound can be heard. That second click stopped happening and I sent back to United Audio. They tested it for weeks, found nothing, and shipped it back and it's been working 3 years on.

Recently we had a huge lightning strike in my yard which skinned a 130 ft tree and popped all the GFCI outlets on the outside of my house.  The only thing inside the house that died was a wireless landline phone base (I still can't figure out why just that) This Marantz is plugged into a Panamax MR4300, however it went back to it's "single click" issue for about two days.  I unplugged and let it sit, did some electronic voodoo spells over it, and it's been working for a month no issues. Now today I'm back to that single click and the amplifier is not kicking on.  I will say everything else seems to be working, including the HDMI board and HDMI pass through in standby.

Has anyone dealt with this issue before/ have a suggestion of what it might be/ how to perma-fix it?
In lieu of that, any class G HDMI friendly receiver suggestions?  Looking for low heat so maybe I can avoid installing vent fan into a cabinet.

Thanks!