we do have exactly similar issue we use Jabra evolve 20 and few engage 50's for our agents and often our agents complaint audio issues like one way audio but when I trouble shoot interactions I can hear both caller and agent voice but they cant hear one another so when I was going through headset setup instructions in resource center
https://help.mypurecloud.com/articles/configure-a-jabra-headset/ Jabra needs some additional software to be installed on user laptops and a chrome extension for call control. this is deployed to be soon in our org and hoping this would resolve the issue. I will post an update once deployed.
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Ajay Kumar Vadluri
Kroll Information Assurance Inc.
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