Confbridge Participant unable to hear

Hi All,

The issue appearing at random for confbridge module i.e. in some cases if a participant joins the confbridge, he/she unable to hear others which make him/her to hangup the call and redial the bridge again. After joining the bridge second time, participant able to hear the other participants.

Listing down the dialplan below (using ODBC MySQL connection for conference bridge numbers lookup);

exten => _X.,1,Answer()

same => n,Set(__FROM_DID=${EXTEN})
same => n,Set(conBridge=${EXTEN})
same => n,ExecIf($["${CALLERID(name)}" = ā€œā€]?Set(CALLERID(name)=${CALLERID(num)}))
same => n,Set(CALLERPRES()=allowed_not_screened)
same => n,Set(TIMEOUT(absolute)=57600)
same => n,MYSQL(Connect connid localhost asteriskuser asteriskrw asterisk)
same => n,MYSQL(Query resultid ${connid} SELECT admin_pin,pin,start_muted,announce_join_leave,quiet FROM confbridge WHERE confno=${EXTEN})
same => n,MYSQL(Fetch fetchpin ${resultid} admin_pin user_pin start_muted_val ann_join_leave_val quiet_val)
same => n,MYSQL(Clear ${resultid})
same => n,MYSQL(Disconnect ${connid})
same => n,NoOp(Conference: ${EXTEN} Admin PIN: ${admin_pin} PIN Number: ${user_pin} Start Muted:${start_muted_val} Announce Join Leave:${ann_join_leave_val} Quiet Val: ${quiet_val})

; Default Profile
same => n,NoOp(Default Profile Without Admin and User Pin)
same => n,Set(CONFBRIDGE(user,startmuted)=no)
same => n,Set(CONFBRIDGE(user,announce_join_leave)=${ann_join_leave_val})
same => n,Set(CONFBRIDGE(user,quiet)=${quiet_val})
same => n,Set(CONFBRIDGE(user,talk_detection_events)=yes)
same => n,ConfBridge(${EXTEN},user_menu)
same => n,HangUp()

exten => h,1,NoOp(Caller: ${CALLERID(name)} left the Conference Bridge Number:${conBridge})

Any ideas which may causing this issue? As Asterisk version Iā€™m using is 11.2.1. Is it a bug? Please advise.