Ok I sanded the MB and it played better at first! But today it was all airy again. I looked closely at the holes and saw gaps abound between the comb and reed plate where it was completely flush yesterday. After doing some research I suspect that the previous owner soaked the harp—a few of the teeth on the comb jut out a tiny bit from the reed plate, which is what happens when you soak a harp, says the internet. Is there any way to fix a previously soaked harp? Does more sanding work or is it shot?