I am also having issues with USB connection on my new EZReader Pocket Pro.
A PC detects the ebook device but transfer of anything >300KB fails with i/o error message.
I've tried 2 different USB cables (including one that came with the device), 2 different computers. Also tried reformating the device and upgrading firmware but so far no luck.
Support is not very helpful so far. First they suggested to reformat/reflash the device. After I reported that it didn't work, i received an email with offer to send me a replacement ... usb cable, and then, if it won't work, they will "try to repair" the unit.
That is after I reported that I've tried 2 different cables and they both work fine with other devices including an older 6" hanlin ebook.