"over current error"

For christmas i got a USB speaker system with CD player. it doesnt dock the ipod, it just has a USB hole that you plug in the wire from the ipod. it works and even charges. but sometimes i get whats called a "over current error" and i have to turn the power off and then on to start it up again. the wire itself is a bit worn, in fact it has a small hole that i covered with electrical tape. works fine with the computer if i want to load something with my itunes. but mexico does use ALOT of electricity and we do have surge boxes. unfortunatly where i have mine set its not near one, so its plugged into a wall. now it only seems to happen when move the ipod around while its connected to the box. i watch movies on it, so i have to hold it in my hand. which if it gets juggled around, the "over current" thing might happen. is there anything else that might cause this "over current error"?

via iLounge Forums http://forums.ilounge.com/itunes-related-mac-pc-applications/279802-over-current-error.html