My apartment neighbor has a shower with a noisy valve. The rushing
noise of the water is very loud in my apartment, and it wakes me up.
It sounds just like the noise my shower valve makes if I turn it on
only halfway.

I need to do something. My neighbor gets up much earlier than me, and
I can't sleep through it, even with ear plugs.

We got one plumber to take a look, and as soon as he heard it, he said
that any shower will make that amount of noise, and there's nothing he
could do. He suggested getting someone to put blown-in insulation in
the wall.

Is there anything else we can try? Could the valve be restricted by
sediment? Would replacing the valve or any of the piping help? Are
there any noise standards for residential plumbing? Are there other
interior wall soundproofing techniques I could look into?

Jimmy