I have been hearing a humming sound whenever any toilet is flushed or any faucet, shower is turned on. The sound gradually gets louder, however it does not vibrate or have a banging sound. I have tried to reduce as well as increase the pressure to see if that would fix the problem but the sound occurs at any pressure level. I don't know what else to try.

Hello summer23

You did not provide details on if this is an old or new problem, and when it started.

Wiki Answers suggest the following solution to this :

"It may be a mild water hammer. You may want to install an arrestor. A water hammer arrestor can be purchased from most hardware or plumbing stores. Or you could just put in a T in a line. The T would need to be installed verticality with a cap on it. Water does not compress, the air in this dead end T will act like a spring giving the flowing water some cushion".

Success !

:)

This is a new problem. I have lived in this house for 4 years and never had any issues. I don't feel like I would need to install any other equipment since the problem is new. The only things I have been doing is adjusting the water pressue up and down. I started to adjust the pressue because my toilets were not filling up fast enough but when the sound started to occur tried to turn the pressue down to make the humming stop but now the humming just occurs at any pressure level.

Most likely candidate is the pressure reducing valve. Open and clean screen. Replace if necessary.

Most likely candidate is the pressure reducing valve. Open and clean screen. Replace if necessary.
Good advice, hkstroud !

Actually the pressure reducing valve is new and was replaced 1 year ago.

I agree with Harold, it doesn't mean if your valve is 1 year old it will not go bad, we remove parts from stock install them on aircraft and turns out to be bad and we call it parts Bad from stock, do as harold suggested and see what happens, see the image below, good luck.

John