Using a DTMF keypad to control a conference

Host participants using telephones or SIP/H.323 endpoints that support DTMF can control aspects of a conference by using their keypad.

For information on using Connect apps to send DTMF tones to another participant, see Using Connect app in-call controls.

Default DTMF controls

The default DTMF controls that can be used within a conference (Virtual Meeting Room or Virtual Auditorium) are:

DTMF digits Control
*4 Toggle presentation in the layout mix
*5 Toggle mute and unmute all Guests
*6 Toggle self mute (see Video watermarking for information about how to enable mute status indicators via themes)
*7 Toggle conference lock and unlock
*8 Cycle through the set of available layouts (this applies to all participants in the conference)
*9 Toggle multiscreen participant display
## Terminate the conference (disconnect all participants including yourself)

† This only applies to the endpoint sending the command, and not to all participants in the conference.

Note that with calls made via the Infinity Gateway, any DTMF signals are forwarded to the other party. The only exceptions to this are interop calls to Microsoft Teams and Google Meet where DTMF controls can be used to control the layout and toggle self mute (see Configuring Pexip Infinity as a Microsoft Teams gateway and Configuring Pexip Infinity as a Google Meet gateway for more information).

Changing DTMF controls

The DTMF digits for each control can be changed on a per-theme basis by editing the themeconfig.json file.

Each control must be two DTMF digits long, and all the commands must be different. When deciding the digits to use for each control, you should ensure there is no risk of overlap in situations where one of the digits is not successfully received.

For example, if you used:

  • 57 to lock the conference
  • 75 to mute all Guests
  • 77 to end the conference

there is a risk that a user could enter 5775 to lock and mute the conference, but due to packet loss the initial digit was not received. In this case the string that is received would be 775, which would be interpreted as 77 and thus a command to terminate the conference.

Disabling DTMF controls

DTMF controls are enabled by default. They can be disabled and enabled on a per-theme basis by editing the themeconfig.json file.