0a784e85_roject___Asterisk_Project_Wiki__Description
[Option] internal_sample_rate [Values] auto, 8000, 12000, 16000, 24000, 32000, 44100, 48000, 96000, 192000 [Description] 
Sets the internal native sample rate at which to mix the conference. The "auto" option allows Asterisk to adjust the sample rate to the best quality / performance based on the participant makeup. Numbered values lock the rate to the specified numerical rate. If a defined number does not match an internal sampling rate supported by Asterisk, the nearest sampling rate will be used instead.
Page Comparison - ConfBridge (v.85 vs v.90) - Asterisk Project - Asterisk Project Wiki
Description