Bat 300x se troubles

Hi, I was wondering if anyone out there ever experienced an issue with their 300x whereby the volume jumps way up all of a sudden when you try to make a small adjustment.

About 2 years ago I sent the system in to get checked out for the same issue and they said it could be due to static discharge confusing the processor so they grounded the volume switch to the chassis.

I just started experiencing the same issue again even when I use the remote to adjust volume.

Many thanks in advance.