Yealink SIP-T23P User Manual page 123

The default codec is G722.
3. Click Confirm to accept the change.
Note
If G722 codec is used for multicast paging, the LCD screen prompts "HD" to indicate that
it is providing high definition voice.
Default codec for multicast paging is configurable via web user interface only.
To send RTP stream via a multicast paging key:
1. Press the multicast paging key when the phone is idle.
The phone sends RTP to a preconfigured multicast address (IP: Port). Any phone in
the local network then listens to the RTP on the preconfigured multicast address (IP:
Port). For both sending and receiving of the multicast RTP , there is no SIP signaling
involved.
The multicast paging key LED illuminates solid green.
The following figure shows a multicast RTP session on the phone:
2. Press the Hold soft key to place the current multicast RTP session on hold.
Advanced Phone Features
113