Usb time out

Dear all,
I just received the USRP hardware. My PC (running SuSe 9.2) supports
the USB 2.0 interface.
I tried to test the basic configuration (using the
test_usrp_standard_rx command) with one RX and one TX and I got the
following messages:
usb_control_msg failed : error sending control message: Connection
time out
and the dmesg shows
usb 4-4 : control time out on ep0out
usb 4-4 : USBDEVFS_CONTROL failed cmd lt-test_usrp_st rqt 64 rq 9 len
ret -110

All ideas are welcome :).