If you have a water pressure regulator, try to reduce the pressu

There are things like "water hammer arrester" but I have limited success with it... I think something like expansion tank will work better, but I haven't tried

http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=expansion%20tank&sprefix=expansion+t%2Caps

http://www.amazon.com/Sioux-Chief-Mfg-660-H-4-Inch/dp/B000H5MQNM/ref=sr_1_1?ie=UTF8&qid=1410196651&sr=8-1&keywords=water+hammer+arresters