Cisco says audible in-band DTMF works reliably only if the call uses G.711 uLaw or aLaw, because compressing codecs distort the tones and can make them unrecognisable to the receiver.
Checked 2026-10-02
- Vendor
- Cisco
- Product
- Cisco Unified Border Element
- Subsystem
- DTMF relay
- Deployment
- on-premises
- Region
- not restricted
- Release range
- current as of 2026-10-02
- Checked
- 2026-10-02
Sources
- Configure DTMF Relay on CUBE — Cisco Systems · tier 2 current vendor documentation · in-band DTMF section
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting DTMF digits not detected in Webex Contact Center flows: source note wxcc-dtmf-troubleshooting-inband-needs-g711. WarmTransfer. https://warmtransfer.net/knowledge/claims/wxcc-dtmf-troubleshooting-inband-needs-g711
BibTeX
@misc{warmtransfer-claim-wxcc-dtmf-troubleshooting-inband-needs-g711,
title = {Troubleshooting DTMF digits not detected in Webex Contact Center flows: source note wxcc-dtmf-troubleshooting-inband-needs-g711},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/wxcc-dtmf-troubleshooting-inband-needs-g711},
note = {Source note wxcc-dtmf-troubleshooting-inband-needs-g711, checked 2026-10-02}
}