Loud clicking from shower valve

I have a Symmons Temptrol shower control. I've noticed over the past several months that, if the valve is turned on slowly (I believe this happens regardless of which position the diverter is in), an extremely loud clicking/banging comes from the control. But if left in that position, it continues to click, shaking the pipes and is quite loud. If you open the valve wider, the sound stops immediately. When shutting off the water, if it is done slowly, that loud clicking starts again until it is completely turned off. It seems to me to be related to air pressure/relief or something, when the valve is within a certain range....forgive my ignorance. No other faucets or showers do this in the house.

Is this something that can be fixed with replacement parts? If so...which parts, there are a number of kits for the Symmons.

Thanks for any help!

Sounds like the valve is in need of a rebuild; a loose part inside of it is most likely the cause of your problem. Contact the mfg of your valve or contact a local plumbing supply to get the parts you need. If you haven't rebuilt a faucet before it might be worth viewing a PDF file on the mfg. website to know how to take it apart and put it back together.