I went out to the store and bought a new USB (belkin usb2.0 to 30 pin) for use with my iphone. It will not mount nor charge. Any idea what could be the issue? The usb cable seems to be good as my Ipod works perfectly off of it. I just downloaded the newest itunes, and I am running a 17" Powerbook, but I tried it on my PC upstairs with 2.0 and it did not see it there either.