All party (telephone conversation taping) State

What is the name of your state? Illinois

Illinois is a State that requires all parties of a phone conversation to be informed that the call is being recorded. Is it unlawful for a private party to say, as some businesses do, that this call MAY be tape for "QUALITY CONTROL PURPOSES"? My concern is that by saying "this call is being taped/recorded" may cause the parties to CLAM UP, for lack of a better term.

That is what is required, notice, it is up to the party at that point how they continue the call.