" I often give my wooden bodied Blues Harps and Marine Bands a quick splosh in water before playing."

I often give myself a quick splosh in water before playing, especially if it's a gig of the better sort. Usually drag a razor 'cross my jowls and slap on some Old Spice, too.

"an old bus ticket crumpled up inside"

If he was a true bluesman, that ticket must've been long as his right arm. Which would certainly explain the poor performance of the instrument.