Drain all the pipes in the house.
Turn off main water, open up all taps and faucets, even outside.
Let them run til dry.
Don’t flush toilets, the fill valves can clog up.
Turn on water, flush air and rust from each faucet one at a time.
Turn off water heater til all this is done.
This should restore the air in the air chambers at all your fixtures, incl your shower/tub.