Symptoms:
After logged in with Workplace CC, the Poly Headset USB work normal in the first call and the next calls (2nd call,3rd call, etc) the headset stop to work. The agent needs unplug and plug the USB to recover the headset. But after one call, the issue come back.
Actions done:
- Updated the Workplace version - not fixed
- Updated the Platronics HUB app- not fixed.
- Reinstalled the Workplace- not fixed
- Changed the Windows sound settings - not fixed
- Enabled Workplace debug logs and found the next messages:
- first call event: 2026-09-23 09:21:42.659 W [16396/csdk] [CSDK::SCPAPI] ENG 0x032d9ec3; 16396: AudioInterfaceWin::UpdateMicrophones (evt:4)
CURRENT Microphones:
[0] Headset Microphone (Poly DA75) guid:{0.0.1.00000000}.{ac2d4aa3-82e1-4fac-ac83-692fe522f376} active external default[ media console communications]
Microphones REPORTED by OS:
[0] Headset Microphone (Poly DA75) guid:{0.0.1.00000000}.{ac2d4aa3-82e1-4fac-ac83-692fe522f376} active external default[ media console communications]
- second call event:2026-09-23 09:37:21.471 W [16396/csdk] [CSDK::SCPAPI] ENG 0x032d9ec3; 16396: AudioInterfaceWin::UpdateMicrophones (evt:6)
CURRENT Microphones:EMPTY LIST
Microphones REPORTED by OS:EMPTY LIST
2026-09-23 09:37:21.471 W [16396/csdk] [CSDK::SCPAPI] ENG 0x032d9ec3; 16396: AudioInterfaceWin::UpdateMicrophones (evt:6)Microphone list didn't change.
The workplace after finished each call, it is sending to the Windows a request to update Microphones List ( device List) but something is happening with the Windows control and the workplace is receiving no microphone available in device list - message from Windows "
Microphones:EMPTY LIST".
Checking Windows KB and others documentation, we found two possible causes:
- Windows KB found with possible bug in the same OS used by Agent's PC: Operating system: Microsoft Windows 11 Pro Version:10.0.26200 Build:26200
- KB MS : https://techcommunity.microsoft.com/discussions/windowsinsiderprogram/kb5124008-issue/4555705
- Something installed in Agent's PC is causing the issue. The customer told us that the PC has installed:
- MS Teams
- AI service monitoring
- Anti-virus and firewall
- Recording application monitoring the PC.
- MS offices and browsers.
Recommendation:
- Test one PC without the "AI service monitoring" and "Recording application monitoring the PC." and remove all unnecessary software. To install old USB sound driver because the Windows updated the USB driver recent.
Status: monitoring the PC without some applications used by customer environment, the issue is not happening. Solved the issue.
Reason: 3rd party Application or Windows USB driver version issue.
