On Sun, 19 Apr 2009 11:34:20 +0100, "John"
wrote:

Washing machine hoses tend to be the cause of this problem - a shockwave
causes them to expand slightly and then cause a sort of recoil. Do you have
several in the house - if they are not really well reinforced then the
problem can be worse.

Only one washing machine but there is also a dishwasher, and I guess
their hoses are the same? Perhaps I should have replaced these? Too
late now but I know for next time. Thanks.