Ringing sound during call

I have heard on one of my systems that there is a soft ringing in the background during a call. It sounds like you are ringing a phone number and waiting ofr the person to pickup… During a conversatio… Its not terribly loud but its verrry annoying and not professional… Anybody else have this issue?

Need way more info to help you. Is this problem manifesting itself when you call between 2 SIP phone? Is it when you call to/from a SIP phone over a trunk? What type of trunks? What version of FreePBX? What version of Asterisk?