Delta Shower Handle

When I had blue pipe, I had no water hammer problems. Since replacing the blue pipe with copper 1 year ago, 21 plumbers have been to my house, most were master plumbers. Some have put: bladder on the hot water heater in the basement new PRV and main cut-off into the house in the basement water hammer arresters on hot and cold hookups to washing machine on the first floor (Prairie Home, IPC "AA" pattern arresters) backwash prevention valve on the water meter in the yard new toilet systems, insides of the tanks, 3 toilets. Strapping on the pipes at the entry in the basement Closing the water supply to every available outlet in the house will not stop it. Water hammer still persists.Sounds like a submarine for a few seconds, followed by 3 loud thumps. Then a few seconds silence. Then the submarine returns for new cycles. Lasts indefinitely. The only way to stop it is to turn the water supply to the house off at the main cut off in the house in the basement. Please give me your best recommendations to find and stop the source of the noise. Thank you.

Am able to get a 25' snake through my sink drain line with difficulty, but have done it several times. Problem is the line keeps immediately stopping up again, or almost so. Have noticed small lumps of white material coming out with the snake. Have also tried using a quart of sulfuric acid to open the line, but that didn't work either. Am totally puzzled on what my problem is. Will appreciate help.