Hi - can anybody throw any light on this problem please? I have just fitted a new Mytime toilet and cistern and everything seemed fine with no leakages and flushing worked perfectly. However, about a minute after the cistern refilled after flushing I noticed a slight hissing sound and the water level started to drop very slowly. After flushing again, the hissing stopped but then starts again about a minute later. The water is not running out of the overflow (as the level is not that high) and it is not seeping into the pan and there is no external leakage, so I am at loss to see where the water is going and why it is hissing. I hope this makes sense to somebody out there - any suggestions would be greatly appreciated as I am busting to try out my new toilet!