First there's the "X-Wing Collector's CD-ROM" from 1994 which runs under DOS and retains the dynamic MIDI music. Graphics are improved to look as they did in the floppy disk version of TIE Fighter, a mixing digital sound system is added, and the Roland MT-32 selection no longer plays the MIDI files specifically made for the MT-32, but plays the General MIDI files with emulation instead.
Then there's the Star Wars: X-Wing Collector Series from 1998 which runs under Windows and drops the dynamix MIDI music in favor of badly recorded .WAV files of the MIDI music and stock music from the Star Wars films. Although the graphics are vastly improved, the musical atmosphere is atrocious. Unfortunately most game reviewers were (and are) too stupid to appreciate original music being composed for X-Wing, TIE Fighter and Dark Forces and actually applauded the use of stock music for Rebel Assault I+II, X-Wing vs. TIE Fighter and Jedi Knight. For Star Wars: X-Wing Collector Series, German GameStar magazine inanely complained that not all of the original MIDI music was replaced with CD-audio based stock music!