Make sure your power supply to the RPi is sufficient . When I first got mine I used an old cell phone charger and I had lost of strange issues. My best guess is tis power relate, either the hub itelf or the hub. Below is a link with verfied working hubs. The cheap ones might not have the juice to power many at the same time.
http://elinux.org/RPi_VerifiedPeripherals#Powered_USB_Hubs