For about the past month or so, we've been getting tons of complaints from end users about audio issues when joining Webex meetings. After some internal troubleshooting, we've found the issue is with users joining Webex from Cisco's own 561/562 wireless headsets.
When these users join meetings they cannot hear or be heard on their mic unless they use the Webex app to test their audio device. We had a similar issue where there was 5-10 seconds of delay with the 56X headsets when someone joined since it seemed like the headset went into a low power mode, but in this new case, the headset will not work at all, regardless of waiting, until they play the test tones in Webex. These users don't have any issues with Zoom or BlueJeans, so it seems like a Cisco/Cisco bug.