Radio Display Fades when hot

I have the same problem with my 2015 Versa Note SV, pretty much since I bought it used in 2016.
Doesn't matter if it's bright or dark out, it depends on the weather. Hot weather makes the radio display dim, sometimes to completely nothing showing.
Recently, the unit just stopped working completely. Then, a couple or few days later, it started working again.

I wonder if all that is related to this electrical issue my car has:

My car has an electrical leak for the last year or two. I've had the battery, alternator and starter all tested, and mechanic says they're great.

If I turn off the car, but continue listening to the radio for a couple minutes (not high draw amplification, just some interview on the radio), car won't start.
If I leave headlights on for 30 seconds after turning off car, car won't start. Then I jump start my car with another car or a battery pack jumper cable, and it starts right up.
This might happen a couple or few days in a row, and then no problem at all for a few days or even several weeks.

A tech recently put an ac/dc clamp meter around my battery cable, and saw that 1.3A was flowing through it, with ALL lights, switches, fans, radio, etc turned off.

Anyone know any solution to all this?

Thanks!
Ted