[Icom] "audio" feedback on am mode

[Bill Steffey]

strange... when i go to am mode,  and bring up the volume, it feeds back???
I can just get enough audio level then it takes of squealing ???
I tired fiddling with the passband, but has no effect in am mode.  ( or at 
least now).. What am I forgetting or is something zonked. It used to be 
fine, I USED AM ON SW ; BDCST & HIGHWAY CB .
I think next step is to un remote the head .  Doesn't seem that a busted or 
crimped remote cable could do this phenomena.

BILL