Double RR

Here is the deal/ this has the GMC dealership I take it to baffled.... or they don't care I get in my truck push the button to start and nothing happens.... FOB has been replaced and other FOB has been used/ NEW battery has been put in and Alternator checks out fine. Here is the deal I can get out loosen the battery cables, hear something resetting under the hood, and then I tighten the bolts back down and truck starts every time. Then maybe 10 times later when I go to get in truck it happens again and I have to go through the battery loosen and tighten process again and then it starts. I have maybe noticed it happens more often when it has rained/ maybe/ but then again it happens off and on all the time. Love to know if anyone has had this happen or has a idea of what maybe wrong