My car on occasion will have a weird sounding EEEEEEHHHHHHHH thing coming from the hatch area. The sound only happens every few days and is either when the car is in drive or idling. I have two 10's in my car and this never happened before I put them in so I am assuming this is the cause,but why? Is it a wiring problem possibly? It doesn't sound like the alternator whining b/c then that would happen all the time right?

 

happens to me in my car when the car is running and the radio is on

 

Have you checked the wires for a short? You might have shot a screw that pierced your speaker cable and it is making intermittent contact with the chassis of the car causing a short.