Avaya 9640 IP Telephone (700383920). The Avaya 9640 IP Phone is the ideal telephone to support productivity enhancing phone applications such as LDAP corporate directories, integration with Microsoft Outlook calendars and surveillance cameras/webcams (refreshed still images). The Avaya 9640 supports higher quality wideband audio in both the handset as well as the speakerphone, which provides crystal clear audio with the elimination of background noise.