Hi all, Inherited a surface thermostatic shower mixer valve in our new home. Guess it's 3-4 years old. "Victorian" design 2 lever - outside - off/on flow rate - inside temperature. Worked fine for a couple of years up to last night when the off/on flow rate lever changed from ~ 120 degree total rotation with "off" at 12 o'clock to continuous rotation - it can be turned round and round. The shower can be turned off if you find the correct position by chance, but it's no longer at 12 o'clock - could be anywhere! It's as if something has come loose inside the mechanism and assuming it's a ceramic disk type operation, the port alignment disk is no longer firmly attached to the operating lever. No operating or fitting instructions handed over. No manufacturer ID. Photo attached. Any ideas re manufacturer/fault finding/repairing gratefully received!