Avaya S8700 Maintenance Manual page 142

Alarms, Errors, and Troubleshooting
The PictureTel 1000 Release 1.1C, PictureTel 6.01 software, and the Vistium 2.0
software successfully rate adapt with the MCU. External rate adaptation
techniques used by VTEL and CLI are known to cause problems with the endpoint
when used with this feature.
Endpoint or I-MUX in Loopback Mode
Some endpoints have a loopback enable feature. This makes S8700
Multi-Connect MMCH data loopback at the MMCH when a connection is in
progress. The loopback can be enabled prior to or during a connection.
The MMCH does not detect the loop and continues to VAS. In most scenarios,
the switch occurs, but within a few seconds, the broadcaster's return video
becomes its own image. Once the broadcaster stops speaking, the system "false"
switches to an apparently random port that was not speaking.
4-68 Issue 1 May 2002 555-233-143