Looking to determine what I can do to get constant radio.

I have had the car since 2012, the radio has a not been kind, but then I have returned that "expression."

As of now the radio will come and go all the time. Mostly not now.

I will be driving along and suddenly its on. Good for 2-5-30 minutes and then off. Days go by, or next day, and the same happens again.

There is no consistency regarding controls, bumps, no bumps, turns, etc.

Chances are the radio is on its way out, most likely a bad solder joint someplace on the mainboard. It's possible it's wiring, but you'll need to yank the unit while it's misbehaving and check the power pins. You can find that info here:
https://www.nicoclub.com/service-manual ... 3%2Fav.pdf