Yes there is a fix. The issue is down to the current build not having USB 1.1 Compatibility (APC USB for mine is 1.1 probably the same for all early ones, mines a Smart UPS 750). The fix is to install a USB 3.0 card in the N54L, that acts as a hub and lets DSM see it correctly. Got mine from here:   DSM 6 now sees it correctly.