Random audio volume spikes

[b514]

Hi guys.
I've been noticing a weird issue with my Expy for a few months now: every now and then the volume of the sound system goes really loud for a split second.
I can't really reproduce the problem, it's pretty random (once a couple days or so). I did notice that it seems more likely to occur when I press the brake pedal or turn the ignition off. But it also occured during normal cruising a few times. I have the 6cd changer + rear Dvd + navigation system.
Any ideas as to what might cause that? Short circuit??

I'm taking the truck in for regular maintenance tomorrow and I'd like to know what to tell them about this. Don't wanna send them on an expensive wild goose chase through the whole electric system. The maintenance itself will already cost me $950 as is (changing spark plugs and everything).

Thanks!
Robert.

 

[Scottandtyson210]

Is it the speed control volume? Not sure if your year has it but you may have the spped control turned all the way up so fluctuation comes with speeds going up and down. Just a thought! I am not to knowledgable on this but just an idea maybe.

 

[b514]

Thanks for the tip. Yes my truck does have that feature. I'll turn it off when i get the truck back and see if this issue still occurs. The truck is in the shop for maintenance now, didn't tell them anything about this issue in the end.