Okay, this is a recent problem. I enjoy putting my Droid Razr in it's car-dock and then connecting my Razr to the car radio via the "in-line" feature that comes with the vehicle.
The other day the Razr wouldn't send the data to the radio. I could make phone calls and listen to music via the Razr's limited speakers, but no sound from the speakers.
So I took the droid to my computer in my office and plugged the speakers into the jack and again, nothing to the speakers, but I can still use the limited Razr speaker.