What is the test for using a tape recording as evidence in a criminal trial?

Appellants first question the vitality of United States v. White, 401 U.S. 745, 91 S.Ct. 1122, 28 L.Ed.2d 453 (1971), which permitted the use of tape recordings of conversations between a government agent and the defendant to be used as evidence in the defendant's criminal trial. White has not been overruled and we are unquestionably bound by it. ⁸ However, appellants claim that White, even if binding, extends only to conversations to which the government agent was a party, not to statements merely made in his presence nor to documents within his view.