Hi jdavemac

It sounds like BIAB is reading the Musescore midi file as a multitrack midi file when it loads it on to the Melody track. If this is the case, then multiple midi channels are present on the Melody track - which is why changing the sound doesn't work. (As far as I understand, changing patches using the mixer is for when the Melody track is only a single midi channel.)

If the above is the case, click on the "Sequencer" button (as shown below). Select the "Melody track" track option when asked.



This will allow you to see all the midi tracks and to change the individual sounds for those tracks. (In the example shown below, midi channels 2, 3, 4, 5, 6, and 10 are present on the Melody track.)



Hopes this helps,
Noel



MY SONGS...
Audiophile BIAB 2025