MacFixIt staffer Lee Marconi writes: "In my case, I've isolated an extension conflict: the SanDisk USB drivers. Details are in this MacFixIt Forums thread (MacOS 9.1 and QuickTime 5.0.2)." See also ...
So my girlfriend just got a new M-Audio Keystation 88es, and she's having problems getting it to work. The drivers for it installed just fine, but none of the midi software recognize that it's there.