batteryxsnare

I guess this applies to Escape and Mariner owners and any other Ford vehicle that has the Mach 300 premium stereo (i think some mustangs do too?)

I have an 06 Mariner and the stereo has an Aux button at the top...what does this do? Does the stereo have an auxiliary input? If so, what type of input is it?

Also, after the stereo has been on for a while, I hear a soft but high pitched noise coming from the front speakers, even when it's off...doesn't sound like alternator hiss because the pitch doesn't change. Does anyone have this problem?

Thanks!