Your problem may be with Quick-time 3.0 and Windows 98. Apparently Apple has said that QuickTime 3.0 has a few bugs in it with '98, and will remap all midi instruments to itself since it apparently can play 40 different kinds of files. When un-installed though, the remap sticks and there is no known way to correct this other than reformatting your hard drive and NOT installing Quick-time 3.0 onto your system.