HI I HAVE THIS PROBLEM ALSO,IT HAPPENS ON ALL TAPS, UP AND DOWN,HOT AND COLD,THE TOILET,SHOWER,WASHING /DISHWASHER,HAVE TRIED TO LOCATE WHERE ITS COMING FROM BUT WHEN YOU ARE DOWNSTAIRS IT SOUNDS DOWN THERE, WHEN YOU ARE UPSTAIRS IT SOUNDS UP THERE HAVE TRIED CLOSING MAIN STOP COCK A LITTLE THAT DOE...
