Customer audio not reaching external application via VB-Cable during W

wt0000 — Thu, 28 May 2026 08:19:27 GMT

1.Issue Description

We are using Webex integrated with an external application via VB-Cable (a virtual audio device). During calls, we are experiencing a case where the customer's (far-end) audio does not reach the external application.

After analyzing the audio logs captured through VB-Cable, we confirmed the following:

The operator's (near-end) audio is consistently captured normally throughout the call.
The customer's audio shows no input at all for a certain period from the start of the call (−91 dB, which we treat as silence).
At some point during the call, the customer's audio suddenly starts coming through (we are detecting levels such as −21.4 dB and −29.9 dB).
Current audio configuration:
- VB-Cable is being used as a virtual audio device.
- "Listen to this device" is enabled.
- Audio analyzed is captured via VB-Cable.

2.Questions

Is there a known behavior in Webex where the far-end (customer) audio is delayed or dropped to the audio output device immediately after a call starts?
When Webex is used with an external system via a virtual audio device such as VB-Cable, are there any known conditions or settings under which the far-end audio is not routed to the virtual device?
Are there any known bugs or reported issues matching this symptom — where only the customer's audio fails to reach an external application while the operator's audio works fine?
- We started observing this issue around May 21st. Were there any releases or changes on the Webex side around that date that might be related?
What kinds of logs or diagnostic information can we collect from Webex to help investigate this issue?

Any insights or guidance would be greatly appreciated. Thank you.

topic Customer audio not reaching external application via VB-Cable during W in Webex for Developers

Customer audio not reaching external application via VB-Cable during W