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Open Settings
Go to System
Open Sound
Check the input and output devices are correct
Change if needed
Close browser
Reopen browser
Test Natterbox
Alternatively, try the steps below and then close the webphone and reopen it.
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2: No CTI popup
Usually, this is a licensing issue, however, this will also occur if you are in an app other than Service Cloud, Sales Console or Natterbox AVS Lightning in Salesforce.
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