BugZero | Cisco BugID CSCvk29692 - DSP detected FXO "supervisory disconnect dualtone ...

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BugZero | Cisco BugID CSCvk29692 - DSP detected FXO "supervisory disconnect dualtone ...

ODD
Cisco
CSCvk29692

Cisco - Defect ID: CSCvk29692

DSP detected FXO "supervisory disconnect dualtone mid-call" is treated as CNG tone

ODD
Cisco
CSCvk29692

Cisco - Defect ID: CSCvk29692

DSP detected FXO "supervisory disconnect dualtone mid-call" is treated as CNG tone

Last updated on February 24th, 2026

BugZero Risk Score
6.1 Medium

Overall: 6.1

Severity: 6.4

Lifecycle: 9.1

Popularity: 4.6

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Bug Details

Description

Symptom

FXO use "supervisory disconnect dualtone" to disconnect the call but call failed to disconnect after disconnect tone is received

Conditions

Both FXO supervisory disconnect and FAX CNG tone detection are enabled

Workaround

no

Further Problem Description

Change history

2026-02-24 Removed: 15.4(3)M

2026-02-24 Removed: 15.4(3)M

2021-09-01 Added: 15.4(3)M

Relevant Products

Click on a version to see all relevant bugs

Affected versions:No known affected versions

Fixed versions: 16.10.1, 16.10.1a, 16.10.1b, 16.10.1c, 16.10.1d, 16.10.1e, 16.10.1f, 16.10.1g, 16.10.1i, 16.10.1s, 16.10.2, 16.10.3, 16.11.1, 16.11.1a, 16.11.1b, 16.11.1c, 16.11.1s, 16.11.2, 16.12.1, 16.12.1a, 16.12.1c, 16.12.1s, 16.12.1t, 16.12.1w, 16.12.1x, 16.12.1y, 16.12.1z, 16.12.2, 16.12.2a, 16.12.2s, 16.12.2t, 16.12.3, 16.12.3a, 16.12.3s, 16.12.4, 16.12.4a, 16.12.5, 16.12.5a, 16.12.5b, 16.3.10, 16.3.11, 16.3.8, 16.3.9, 16.6.5, 16.6.5a, 16.6.5b, 16.6.6, 16.6.7, 16.6.7a, 16.6.8, 16.6.9, 16.8.2, 16.8.3, 16.9.2, 16.9.2a, 16.9.2s, 16.9.3, 16.9.3a, 16.9.3h, 16.9.3s, 16.9.4, 16.9.4c, 16.9.5, 16.9.5f, 16.9.6, 16.9.7, 17.1.1, 17.1.1a, 17.1.1s, 17.1.1t, 17.1.2, 17.1.3, 17.2.1, 17.2.1a, 17.2.1r, 17.2.1v, 17.2.2, 17.2.3, 17.3.1, 17.3.1a, 17.3.1w, 17.3.1x, 17.3.2, 17.3.2a, 17.3.3, 17.3.3a, 17.3.4, 17.3.4a, 17.4.1, 17.4.1a, 17.4.1b, 17.4.2, 17.5.1, 17.5.1a, 17.6.1

Relevant Products

Click on a version to see all relevant bugs

Affected versions:No known affected versions

Fixed versions: 16.10.1, 16.10.1a, 16.10.1b, 16.10.1c, 16.10.1d, 16.10.1e, 16.10.1f, 16.10.1g, 16.10.1i, 16.10.1s, 16.10.2, 16.10.3, 16.11.1, 16.11.1a, 16.11.1b, 16.11.1c, 16.11.1s, 16.11.2, 16.12.1, 16.12.1a, 16.12.1c, 16.12.1s, 16.12.1t, 16.12.1w, 16.12.1x, 16.12.1y, 16.12.1z, 16.12.2, 16.12.2a, 16.12.2s, 16.12.2t, 16.12.3, 16.12.3a, 16.12.3s, 16.12.4, 16.12.4a, 16.12.5, 16.12.5a, 16.12.5b, 16.3.10, 16.3.11, 16.3.8, 16.3.9, 16.6.5, 16.6.5a, 16.6.5b, 16.6.6, 16.6.7, 16.6.7a, 16.6.8, 16.6.9, 16.8.2, 16.8.3, 16.9.2, 16.9.2a, 16.9.2s, 16.9.3, 16.9.3a, 16.9.3h, 16.9.3s, 16.9.4, 16.9.4c, 16.9.5, 16.9.5f, 16.9.6, 16.9.7, 17.1.1, 17.1.1a, 17.1.1s, 17.1.1t, 17.1.2, 17.1.3, 17.2.1, 17.2.1a, 17.2.1r, 17.2.1v, 17.2.2, 17.2.3, 17.3.1, 17.3.1a, 17.3.1w, 17.3.1x, 17.3.2, 17.3.2a, 17.3.3, 17.3.3a, 17.3.4, 17.3.4a, 17.4.1, 17.4.1a, 17.4.1b, 17.4.2, 17.5.1, 17.5.1a, 17.6.1

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