Getting segfault at 10 ip .. error 4 in app_queue.so

Hi group

I received this today unfortunately on a busy (for us anyway) 13.15.1 Asterisk system:
Sep 21 14:07:44 3037-QGPSC-CM1 user.info kernel: asterisk[1110]: segfault at 10 ip 00002b1ed1d4882c sp 00002b1ed728fcd0 error 4 in app_queue.so[2b1ed1d34000+35000]
Sep 21 14:07:45 3037-QGPSC-CM1 user.info safe_asterisk: Asterisk exited on signal 11.

Here is my offending dialplan:
[subDialCustom-Queuegroup]
;ARG1 - Extension, ARG2 - CF and max queue time destination dial plan
exten => start,1,Gosub(subSetConn,start,1({ARG1},Queue Group)) ;Set ext_cid for when a call is forwarded externally same => n,Set(__ext_cid={IF([{DB_EXISTS({ARG1}/ext_cid)}]?{DB_RESULT}:{ext_cid})}) same => n,GotoIf({DB({ARG1}/cfa)}?cfa) same => n,Set(queue_options={IF([{DB_EXISTS({ARG1}/queue_options)}]?{DB_RESULT}:)})
same => n,ExecIf({DB({ARG1}/natimer)}?set(queue_timeout={DB({ARG1}/natimer)}:set(queue_timeout={default_natimerqg})) ;Set and check announcement file same => n,Set(announcefile={IF([{DB_EXISTS({ARG1}/welcome_ann)}]?announce{DB_RESULT}:)})
same => n,Set(announcefile={IF([{DB_EXISTS({DB_RESULT}/audiofile)}]?{DB_RESULT}:{announcefile})})
same => n,GotoIf([{ISNULL({announcefile})}]?bypass_filecheck) same => n,ExecIf(["{STAT(e,{monitor_path}{announcefile}.wav)}"="0"]?Goto(no_welcome_file)) same => n(bypass_filecheck),Answer same => n,ExecIf([{ISNULL({announcefile})}]?NoOp(Do nothing):Playback({monitor_path}{announcefile}))
same => n,Queue({ARG1},,,,10) same => n,MusicOnHold(default,1) same => n,Queue(Qoverflow1,,,,10) same => n,MusicOnHold(default,1) same => n,Queue(Qoverflow2,,,,10) same => n,MusicOnHold(default,1) same => n,Queue(Qoverflow3,,,,300) same => n,Hangup same => n(cfa),Dial(Local/{DB({ARG1}/cfa)}@{ARG2})
same => n,Hangup
same => n(no_welcome_file),Log(WARNING,Welcome announcement {announcefile} for Queue {ARG1} does not exist)
same => n,Hangup

queues.conf is attached

Any ideas. What should I do next for troubleshooting?

Thanks
Mike

queues.conf.txt (12.8 KB)

Maybe this: https://wiki.asterisk.org/wiki/display/AST/Getting+a+Backtrace