On a computer that is running Windows Server 2003, Microsoft Office Communications Server 2007 R2, Audio/Video Conferencing Server is running alongside other Office Communications Server 2007 R2 services.
Either Performance Monitor or the Logman.exe command-line tool logs more than 1,000 performance counters per second on the Audio/Video multipoint control unit (AVMCU).
In this scenario, there is a contention with CPU resources. This contention is between the real time processing that is required for the AVMCU and the performance counter logging. This contention affects the real time performance of the AVMCU. Then, audio quality issues occur for audio conferencing users.
To work around this issue preventively, do not enable logging of more than 1,000 performance counters per second in Office Communications Server 2007 R2, Audio/Video Conferencing Server.