> For a complete documentation index, fetch https://docs.voximplant.ai/llms.txt

# DTMFType

## Values

All types of DTMF tones trigger the `CallEvents.ToneReceived` event: in-band , RFC 2833 and SIP INFO. Receiving an RFC 2833 tone disables processing of in-band tones to avoid duplicating

Only RFC 2833 DTMF tones trigger the `CallEvents.ToneReceived` event

Only in-band DTMF tones trigger the `CallEvents.ToneReceived` event

Only SIP INFO DTMF tones trigger the `CallEvents.ToneReceived` event