Your computer may not be fully supported by the Qio BIOS. If you boot with SxS cards inserted into the Qio, it forces allocation of the busses and memory space needed. Some computers will refuse to allocated bus space for later insertion unless two SxS cards are inserted before booting.
If you are having hot plug issues, not basic SxS functionality, you can use CFScan utility to force the Qio to "see" a newly inserted device.
