I have a 2001 lesabre, and radio was working fine until recently its like if i have the volume knob way down, it will all of a sudden start playing music VERY loudly and then goes up and down without me touching the volume knob? has anyone experienced this and if so, what can i do? i went a bought another buick factory radio and it does the same thing, so i know its not the radio--any help will be appreciated

Just in thinking,

There is of course the circuit going to your steering wheel volume control that may be effecting it.

Without knowing what you are seeing, there are other possibilities such as your antenna line is intermittent.