Cisco devices use RTP payload types 96 and 97 for fax by default, and if a third-party device uses 96 or 97 for DTMF, Cisco recommends changing the fax payload type on both dial-peers or using asymmetric payload dtmf.
Checked 2026-10-02
- Vendor
- Cisco
- Product
- Cisco Unified Border Element
- Subsystem
- DTMF relay
- Deployment
- on-premises
- Region
- not restricted
- Release range
- Cisco IOS XE 17.6 onwards
- Checked
- 2026-10-02
Sources
- Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - DTMF Relay — Cisco Systems · tier 2 current vendor documentation · chapter 'DTMF Relay', payload type note
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting DTMF digits not detected in Webex Contact Center flows: source note wxcc-dtmf-troubleshooting-cube-pt-96-97-fax. WarmTransfer. https://warmtransfer.net/knowledge/claims/wxcc-dtmf-troubleshooting-cube-pt-96-97-fax
BibTeX
@misc{warmtransfer-claim-wxcc-dtmf-troubleshooting-cube-pt-96-97-fax,
title = {Troubleshooting DTMF digits not detected in Webex Contact Center flows: source note wxcc-dtmf-troubleshooting-cube-pt-96-97-fax},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/wxcc-dtmf-troubleshooting-cube-pt-96-97-fax},
note = {Source note wxcc-dtmf-troubleshooting-cube-pt-96-97-fax, checked 2026-10-02}
}