As it is right now, bards are fun and helpful. But not for their music, that part drives people CRAZY.
They play the same tune over and over, using the same few notes, on the same instrument, for hours.
What would make bards weird and wonderful like they should be is access to higher and lower octaves, as well as a variety of instruments:
Holding the trigger on either mallet could increase or decrease the octave of the notes being played, allowing for a range of 21 notes instead of 7.
Possible instrument changes could include replacing the xylophone sound with the blocky clonk of wood blocks. The deep rumble of hide drums. The Caribbean twang of steel drums. Even the haunting tone of a pipe organ.
With these tools, bards could go from your baby brother smashing his toy xylophone in the other room to legitimate entertainers.
(Also access to a drum sound would make it much easier to mask how bad your playing is, because the frantic smashing would just be the uprising cacophony of war drums.)