how do i know if my phone is tapped?

unless you have the knowledge to know how the telephone system works, there is no way for the user to know if the phone is "tapped".

If you think it is, ask yourself WHY would it be tapped? Are you operating a meth lab?

If you are, then it probably is tapped.

You don't.

Noise, static, buzzes, hisses and clicks on a phone line mean nothing except that some part of the circuit between you and the person you called is not in perfect condition.

If it is tapped legally - with a warrant - then no one will tell you.

If it is tapped illegally - then no one but the person doing it will know.

there is no way to know that it is currently being wiretapped....

the only way to know that it has been wiretapped in the past is not an answer that anyone would like to hear... evidence presented to a judge gathered from wiretapped conversations...