Some easy ways to fix this problem along with a couple of useful devices if you are at your wits end.
If you would like a Shock arrester, as in the video, here is the Amazon link. https://amzn.to/2LERZ2I .
If you would like a pressure reducing valve, as in the video, here is the Amazon link. https://amzn.to/2LF8hZi
Also you can now visit my Amazon store for more parts at http://www.amazon.co.uk/shop/dereton33