you can try turning on all the taps at once, and flushing at the same time, there could be air in the lines......
air in pipes. have you shut the water off for a period of time like in a vacation house?
it not air in the line sound like your pipes cast iron they sre rusting and inside are rusting inword making the size pipe be smaller this cause the sound like a train .not getting the write size venting air for it to flow i've sen this a lot this need to be replace to stop the sound and it what be long before you have back up of waste in your house
Try this first ... http://www.realtor.com/home-garden/do-it-yourself/plumbing/installing-shock-arrestors.aspx?source=web
check your water pressure if it is too high pipes will vibrate or whistle.
There are several common types of plumbing sounds in residential construction. A ticking sound is usually ABS waste and vent piping expanding when hot water is run, and sounds like water dripping in the wall. It is a normal occurrance in wood frame construction and service to correct is most often declined. (The cure is worse than the cold.) banging pipes can be a combination of high pressure, loose piping that was not secured properly, and sometimes it is from loose washers or other parts in faucets that vibrate when the water is turned on and the sound transmits through the piping and can be quite loud. Pressure regulators will also make noise as they begin to go on the fritz. Please call us if you would like Grant or myself to come by for an evaluation, free in most areas. Core Plumbing 858-538-6025
Agrees with Vincent Plumbing...It's a Good Link!
Make sure your angle stop behind the commode is open all the way sometimes on some stops if they are not open all the way the valve will flutter and make a really loud humming noise in the wall. If it is a banging sound then try arrestors.