Article ID: 957648 - View products that this article applies to.
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When one or more Microsoft Office Communications Server 2007 clients report packet loss, audio quality decreases during a conference call that is hosted on a Communications Server 2007 Audio/Video Conferencing Server.
This problem occurs when the Forward Error Correction mechanism is turned on because of the audio packet loss. This causes corruption of the contributing source (CSRC) list. The CSRC list is used in the Communications Server 2007 Audio/Video Conferencing Server to mix the active speech sources in the conference. A corrupted CSRC list affects the audio mixing process and the overall quality of the audio in the conference call.
To resolve this issue, follow these steps:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about the components, about the protocol, and about the architecture of Communications Server, download the technical document on the following Microsoft Web site:
Article ID: 957648 - Last Review: January 15, 2015 - Revision: 3.0