Car mount charging issue?

[Rjeff33351]

I recently purchased a droid x, the verizon standard car mount and a griffin itrip fm transmitter w/ the usb charging port. With everything hooked up my phone will charge in the holder for about 5 mins before the disconnected banner comes up saying unplug the chager from the port to save energy, and then the phone will not charge. Im wondering if anyone else has this problem? or is it just possibly a bad fuse or something in the itrip system? thanks!