User Guide for the CP920 HD IP Conference Phone4Item Description⑯ USB Port• Allows you to connect a USB flash drive (optional) to yourphone so you can record calls/conferences and play backrecorded files.• Allows you to connect expansion PSTN box(es) (optional)to experience calls in PSTN. Up to two cascaded expansionPSTN boxes can be connected, so you can experience thelocal five-way conference conveniently in excellent speechquality with PSTN.Icon InstructionsCertain features and icons do not apply to PSTN. Therefore, not all icons listed in the tablebelow will display when using PSTN only. Please refer to the relevant sections for moreinformation.Icons appearing on the LCD screen are described in the following table:Icon DescriptionNetwork is unavailableRegistered successfully (Yealink Cloud account)Registered successfully (SIP/PSTN account)Hands-free (speakerphone) modeVoice MailAuto AnswerDo Not Disturb (DND)Call HoldCall MuteRinger volume is 0Phone LockCall Forward
