I/S Radio, FM Volume Problem

[BINOVC]

Hello, new to forum (except I recently bought Bon's digi-sync from here!), with a new-to-me 2000 I/S.
The PO advised me that there was possibly a "loose wire somewhere" due to radio/speaker issues.  What I have found is that the radio volume while on FM will randomly drop significantly.  When this happens, if I previously had it set to about level "10", I have to crank it up to about "20" (or so) to be able to listen.  Of course when it randomly "corrects" then the speaker volume about blows me off the bike!
The AM band does not seem to have the problem as the FM band.
I have tested it with ambience both on/off, and also the AVC on/off.
This happen to to others?  Any recommendations?
Thanks!

[gordonv]

My question would be is this while parked or driving?

You've already mentioned about the AVC, so that works while moving at speed.

[Bighead]

My question would be is this while parked or driving?

You've already mentioned about the AVC, so that works while moving at speed.

AVC = automatic volume control. The faster you go the louder it gets but it isn't gradual mine gets louder at about 55 then more at 65 and yes it gets really loud and drops sharply when decelerating.

[BINOVC]

My question would be is this while parked or driving?

You've already mentioned about the AVC, so that works while moving at speed.

It can happen at any time, moving, stopped, engine off.  The AVC appears to be working normally, whether or not the volume is misbehaving.

[Steve K (IA)]

The first thing I would do is open up the radio control box on the left handlebar and spray contact cleaner in all the switches. 

[mustang071965]

had a issue like this with my 99 IS. the heads up display showed the avc working and when i reached around 45 mph to 50 mph the avc kicked in. then hit a small bump in road and the sound dropped like the speaker + and - wire where crossed. i inspected the speaker connections and found them to be tarnished ( gray coated ) thats tarnish. so i cleaned the connectors and added dio grease. then i checked the radio connectors under the seat. they where lose. i cleaned the pin holes with a pin hole cleaner ( can be found at your local radio shack ) put dio grease and reconnected. all has been well for the last 6 years now.

[BINOVC]

Thanks all so far, I will be looking into this again soon.  Right now I'm in the middle of ball joint r/r on my F-150, so gotta finish that up first.