We have a banging (water) pipe / vibration noise problem that just started about 3 days ago when we flush the toilet in our master bathroom.

It appears to occur several seconds after flushing... when the water tank is finished refilling and the water shuts off.

Although we've isolated this problem to one toilet (other faucets, showers, tubs, and toilets don't cause the noise), a similar but less vibrating sound occurs when we run the washing machine or use the water dispenser on our refrigerator.

I thought I'd start troubleshooting with the toilet, since its noise is the most pronounced. And if it's helpful, our toilet valve/ball mechanism is a FluidMaster 400A.

We have several water pipes that I can see in the ceiling of our basement, water lines that go to other parts of the house, but I think the troublesome toilet, washing machine and refrigerator are fed by the same line... since all three of them are on the same side of the house in proximity to each other (1st floor: washing machine and refrigerator. 2nd floor: master bedroom toilet).

I can't think of anything that we've done differently or unique before the noise started a few days ago.

Any suggestions would be greatly appreciated.