DVD on the FM?

[HummerNewbie]

I used the FM modulator on mine last night and it worked great for about 5 minutes. For some reason all of the sudden something else started playing through the stereo. I had stopped somewhere and left it running as there were a couple of people in the vehicle. Seemed to happen when I got out of the drivers seat. Didn't mess with it, they just went to the headphones. When I got home, hadn't shut the H3 off yet but when I got out the driver side player shut off. I am wondering if there is a loose connection or something since both times something happened, I was getting out of the drivers seat.