i purchased this an EasyAcc 7 Ports USB 3.0 HUB with 12V 3A Power Adapter and 3ft USB 3.0 Cable for iPad iMac Macbook Acer Laptop Utrabook PCs [with VIA VL812 Chipset] from amazon last week but im having problems with it and was wondering if anyone could help i have it connected to my new imac 27" running mavericks osx when i try to copy files from the imac to usb 3.0 usb sticks which are plugged into the hub it gets so far then crashes every time. ive tried plugging the sticks directly into the imac and copying the same files and it works perfectly does anyone have any ideas ?