Motorola W755

Our phone has dismal, unacceptable outgoing voice quality when used with a wired headset. We've tried 3 different headsets, nothing cheap - various models of Plantronics. (We have not tried Bluetooth yet. And it works fine with no headset.) We exchanged the phone, and the outgoing voice quality is hardly any better. Fortunately they didn't log it as an exchange, so we still have another chance. Is anyone else having the same issue? It's like it has too much noise canceling or something.