20002 Radio/CD Volume Control

I just spent the last 2 days tearing apart my bike to try to figure out why the up volume control will not work my 2002 K1200LT. It just stopped suddenly last week while riding. The down volume control works on both the handle bars and rear passenger control. All other functions on the multi switches check out. The multi swithches themselves check out. Tried disconnecting one switch; same result volume down works but volume up doesn't work. Yhe only way to reser the unit is to disconnect the battery and let it sit for a few minutes while it resets itself then I at least have volume at the factory preset level.

Suggestions or is the radio/CD toast??