voice-gateway-service/pjproject/pjlib/include/pj/config_site.h

#   define PJSUA_MAX_CALLS              512

#	define PJSUA_MAX_ACC                       32
#	define PJSUA_MAX_PLAYERS                   32
#	define PJSUA_MAX_RECORDERS                 32
#	define PJSUA_MAX_CONF_PORTS                (PJSUA_MAX_CALLS+2*PJSUA_MAX_PLAYERS)
#	define PJSUA_MAX_BUDDIES                   32