i was wondering if anyone could help me. i have a small condo with upstairs and downstairs bathrooms. recently with the colder weather approaching here in VT the pipes have been rattling very loudly but only in the evening. it sounds almost like a jack hammer. heres the thing....when i turn off the water to the upstairs toilet nothing happens but when i turn off the water on the downstairs toilet it cures the pipe problem. also and i dont know if this has anything to do with the same problem but the upstairs toilet seems to never stop cycling at night also....it does fine in the day but cycles almost all night....it will fill tank then when tank is full the volume of the cycling decreases but there is still noise and it will go for hours. someone please help me im baffled! the condo was built in the early 80's and ive only lived here a few months.