Problem USB interface, otherwise ok

The USB interfaces remain often times depend up to 10 seconds, more rarely total. That's what happens when I switch between two computers keyboard and monitor back and forth (by the way only at this board, the other has a computer ASUS board because that does not happen; Between two ASUS boards which also does not happen). Sometimes the board switches from USB briefly, so that the electronic interfaces switch the computer changes. If I then turn back by hand, USB hangs often. The board is presented with C2 stepping. The problem I had immediately noticed but considered bearable. Today I would not recommend and buy the board for this reason.

I run the Rchner with
Win7 64bit, 16GB, SSD.
Usually I am not Locke as admin, but for safety reasons as users without administrator rights. I handle on all my computers that way.

Update 1/11/2015:
Review of three reduced to a Star!
Why: I wanted to back up my plate now as usual "C" with True Image 2011. And I shall, as always, with a TrueImage2011 (formerly 2009) produced a Rescue CD, with which the computer is booted. In this "Asrock H87 PRO4" board but the USB ports are in this case not released, so that the program also can not be operated - this is useless!
The same approach I use with an ASUS board, in which everything works fine.

I have the Board now has four months in operation and regret that I did not immediately returned, because there were problems from the start with the USB interfaces.
I can not recommend the Board.