Comment 12 for bug 1095315

Looking a bit at the snd_usb_fasttrackpro_boot_quirk function, it calls usb_driver_set_configuration, which has the following comment:

  * Device interface drivers are not allowed to change device configurations.
  * This is because changing configurations will destroy the interface the
  * driver is bound to and create new ones; it would be like a floppy-disk
  * driver telling the computer to replace the floppy-disk drive with a
  * tape drive!

And then goes on that in special circumstances it might be needed anyway. So; it sounds like this creates a race somehow.

I'm not sure why we want to switch to configuration "2" in the first place, but if we are, it would make sense not to continue making the actual card but just quit out as early as possible.

What if we made the function return an error instead? Could you try the attached patch and see if it helps?

Also, could you attach the output of lsusb -v for completeness?

Thanks!