0a784e85_roject___Asterisk_Project_Wiki__Description
[Option] mixing_interval [Values] 10, 20, 40, 80 [Description] 
Sets, in milliseconds, the internal mixing interval. By default, the mixing interval of a bridge is 20ms. This setting reflects how "tight" or "loose" the mixing will be for the conference. Lower intervals provide a "tighter" sound with less delay in the bridge and consume more system resources. Higher intervals provide a "looser" sound with more delay in the bridge and consume less resources
Page Comparison - ConfBridge (v.85 vs v.90) - Asterisk Project - Asterisk Project Wiki
Description