Indeed, I hear no difference whatsoever between the trombone in MuseScore_General for MU3 and MS Basic for MU4. Make sure you've actually selected trombone as your instrument. If you continue to have trouble, please attach the specific score where the trombone sounds other than it should.
Comments
Mu4 uses the very same sound.
Unless you mean Muse Sounds rather then the builtin soundfont (in which case using the MS Basic sound us the workaround
Indeed, I hear no difference whatsoever between the trombone in MuseScore_General for MU3 and MS Basic for MU4. Make sure you've actually selected trombone as your instrument. If you continue to have trouble, please attach the specific score where the trombone sounds other than it should.