trans slips

Hey Guys, I have an issue with a 03 Rincon. The thing will not stay in gear. With just the ignition on and the transmission in gear not running you can hear solenoid "A" (black) clicking and the shift indicator jumping from 1 to 2. With the machine running as I drive it, it moves in 1st gear...

I recently purchased a Rancher 4x4. Not totally sure what year model i have here, but not really relevant anyways. I assume...? Previous owner remarked he had recently put rings in it. Fair enough, atv does'nt smoke, lotta power, 75% runs like its fresh off the assembly line. At initial...