As standard equipment should be connected dock here a headset, keyboard, mouse and BlackBerry.
With up to three devices, this was not a problem, the device ran all normal.
When connecting 4 or more units irregularly and alternately fall from the equipment. It definitely can not be due to the various devices as described fail this independently and function after plugging again.
For an active USB Hub is a completely inadequate function, this performance would have a passive 4 Port Hub also provided.
Thanks to Amazon, the equipment has been returned without problems.