Every time we run two water 'devices' such as the sink tap and flush the toilet, or use the washing machine and run tap, a loud vibrating sound comes from the water pipes in the walls. This has started to happen when just one 'device' is on but for only a short period (few seconds but very loud). Is there something I can do to stop this? Many thanks.

Your house PRV valve may be starting to go bad. Go to the PRV and have someone flush. See if the noise comes from the valve. I just had to replace one in a rental house and it was the same issue.