Anybody share me the background noise suppresion?

Hi all,
I have designed a cordless telephone,but the background noise is uncomfortable,i want to improve it.Anybody kindly share me your experiment and documents about how to suppress it?
Thank you.

Is it related to the PCB design?

Anybody?

if it si from external source then u can use a pass filter to eliminate.U can use some decouplers where ever necessary.

It is difficult that mixed with audio,for it is white noise .so i want to find the root source.what is the root cause?

Anybody kindly tell me how to reduce the background noise in FM system?