Have a new style loo that is "noisy" when flushing (seems that pipes are reverberating when the cisterb is filling up). It's in a rental flat in Crowthorne (which is now available btw), and needs sorting.
David, if there"s an inline isolator on the supply, try turning it while the cistern is refilling. It may be just a pressure thing and adjusting the isolator may be all that's required. If that doesn't fix it, I'm all out of ideas. HTH?
Thanks chaps. What on earth do these isolator valves and flow restrictors look like, and where will I find them. The pipes run overhead and into the ceiling void, so can't get at them, but they aren't touching anything - I think