The QL-SD driver ROM is so full that every byte counts and during my search for superfluous bytes for v1.09 I removed one instruction too much. This results in a wrong value returned from the iof.rhdr call which is often not used anyway but can lead to subtle bugs in applications. Today I’ve uploaded a bug fix release 1.10 which only addresses this one problem and all users of 1.09 should update. If you don’t have the means to update the ROM the resident driver could also be loaded during boot (in case of the GoldCards this can make sense anyway as the driver is executed faster from RAM than from ROM).