Hi All, We had a new shower fitted last year and over the past few months we have noticed an ever increasing horrible squealing sound when its on. To give as much info as possible its a Mira 9.5kw Electric Shower and is in the en suite with the water tank in the loft. We have a hot water tank on the landing. When the shower is turned on and the dial set to high but cold the water shoots out and no noise is heard. When you turn the dial towards the red dots the pressure drops and the squealing starts. If i shake the shower hose the squealing noise changes as well. If i turn the shower to the last red dot it becomes red hot and the squealing quietens down. I have also noticed that a build up of a reddish brown stuff is visible around the shower head nodules after 2 or 3 weeks use. Any ideas how this noise can be stopped as its doing my head in when i want to get a shower.