Finally - i tried another approach on getting good datarate out
of the FX2 device.

I started a kernel usb module, which recognizes my fx2 hardware.
There are 2 modes:
normal read - synchronous USB READS. Works but just provides 4 MS/s

asynchronous reads. does not work - create kernel crashes

this mode can be set by setting USB_OPENRADIO_MULTI define statement
this module mainly crashes when

* data is actually read
* FX2 is disconnected

Would be very nice of any of you could look at the code
(its not big though 12 KB ) to find out if there are very basic mistakes
inside

Please grab my code from

http://194.208.18.155/driver.tar.gz