User Guide for the SIP-T20P/SIP-T20 IP Phone60You can press a call return key to place a call back to the last incoming call.To configure a call return key via phone user interface:1. Press .2. Select Features->DSS Keys.3. Select a desired DSS key.4. Press or to select Key Event from the Type field.5. Press or to select Call Return from the Key Type field.6. Press to accept the change.Call return key is configurable via web user interface at the path DSSKey->Line Key.You can mute the microphone of the active audio device during an active call, and thenthe other party cannot hear you.To mute a call:1. Press during an active call.The LCD screen indicates that the call is on mute.To un-mute a call:1. Press again to un-mute a call.You can place an active call on hold. Only one active call can be in progress at any time.Other calls can be made and received while placing the original call on hold. When youplace a call on hold, your IP PBX may play music on hold to the other party whilewaiting.2. Key Type:◄ Call Return ►1234Mute 01:20