High quality sound HD audio offers a clear and natural sound. The omnidirectional microphone and full-duplex allows meeting participants to be heard and involved in the meeting.RMA-Abwicklung nur mit einer Freigabe vom Hersteller möglich. Registrierung/Vorgehensweise unter: https://support.yealink.com/en/portal/knowledge -> KnowledgeBase -> FAQ -> Services -> How to report RMA.