Consider the following schenario:
You enable the media bypass setting in a Microsoft Lync Server 2010 or Lync Server 2013 environment.
A user signs in to Microsoft Lync 2013.
The user makes a call to a public switched telephone network (PSTN) telephone that is connected to version 8.6 of Cisco Unified Communications Manager (CUCM).
In this situation, the call is disconnected.
This issue occurs because a 151 kilobits per second (Kbps) value of bandwidth is required by G.711 u-Law. Therefore, when a call is in an environment in which bandwidth is less than 151 Kbps, media manager sets the bandwidth to 151 Kbps incorrectly.
To resolve this issue, install the following update:
2889929 October 2014 update for Lync 2013 (KB2889929)
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