When we flush the toilet, it makes a loud humming sound toward the end of the flush cycle, as the water fills up. Once the water has filled, the humming stops. What could be causing this, and how do I go about repairing it?

Thanks in advance!

:confused:

You have a toilet troll... you need to call in a specialist! :D hehehe

Nah, jokes aside:

Lift the cistern lid and press down on the polystyrine ball that regulates the water level in the cistern. The pipe should start letting water in. if the humming noise is there, there could be something within the piping. If it is not, and it only happens when you flush, try holding the poly-ball up while you flush - letting no water through to refill the cistern. Doing things like this will allow you to pin-point where the noise comes from and when.

I don't recommend trying to fix it yourself, call a plumber. By going through the elimination process yourself you can tell the plumber exactly when and where the noise comes from.

:)

Try and turn your water pressure down, as long as you still have enough pressure at other taps and works, probkem solved...

The problem is the rubber washer in the ballcock fill valve. You can usually open repair, clean these washers or diaphrams but I don't know what model you have. The washer/diaphram is fluttering just when it is ready to close.