Assume that a Microsoft Skype for Business Server 2015 server is experiencing high latency. In this situation, when you dial into a conference, you experience long periods of silence. This is caused by the latency on file I/O operations to the server.
Additionally, after you turn off name recording by running the Set-CsDialInConferencingConfiguration -EnableNameRecording $false cmdlet in this situation, you continue to experience the same issue.
To fix this issue, install the November 2016 cumulative update 6.0.9319.272 for Skype for Business Server 2015.