I had a new toilet installed (Vitra brand) professionally about 3 weeks ago. Worked fine until this morning when it was flushed it really sounded like a motor was running.. very loud... coming from the tank. The toilet takes little water.. (in the bowl and fills about half in the tank) Has lots of force in the flush... is this something we're going to have to live with or should I call the plumber back to fix something? Thanks

Which ballcock is yours? (see image) You might try reducing the volume at the angle stop to see if that helps. Goood luck, Tom

I know where Tom may be going and he can help you fix it. However, I also know if I paid a pro 3 weeks ago I'd be calling him back for HIM to repair it. A pro will expect a certain number of call backs and wants his reputation to be good so he'll fix what's wrong for no charge.