Adjusting volume on rotary joystick causes cruise speed to drop

[Weaklink]

2017 21vlx, as in title attempting to adjust stereo volume using rotary joystick causes speed control to drop or sometimes cruise speed will drop randomly. Searching didn’t turn up much. Tried working joystick through its movements in case it was sticking without much luck. Any other ideas? Just got it out of the shop and hate to go back. 

[Eagleboy99]

Finally!  Proof that wakesurf boats don't work without stereos! 

[ahopkins22LSV]

If you push the knob up and down it will adjust the cruise speed. Rotating the knob should only adjust volume. I’d double check wire connections. Should just be one plug on the back. If that is good the knob might be defective, or maybe the programming, and probably time to get your dealer involved. 

[Weaklink]

Yes I’m familiar with how the knob works. I thought maybe I was being too heavy handed and inadvertently pushing down but no.....I’ll check the connection as the boat was in last week with flickering maliview which ended up being a loose cat 5 connection. Maybe something was bumped during that repair. I hope it’s that easy.