Asterisk does not send disconnect

I have below setup for incoming calls to my asterisk:

include => residential-include

exten => s,1,SetMusicOnHold(default)
exten => s,2,Set(TIMEOUT(digit)=5);
exten => s,3,Set(TIMEOUT(response)=5);
exten => s,4,background(silence/1)
exten => s,5,Background(pls-wait-connect-call)
exten => s,6,Background(silence/5)
exten => s,8,Monitor(wav,${CALLFILENAME},m)
exten => s,9,Set(CALLERID(number)=91${CALLERID(NUM)});
exten => s,10,Dial(SIP/7087771111&SCCP/7087771111&IAX2/7087771111&IAX2/outside,15)
exten => s,11,GotoIf($["${DIALSTATUS}" = “NOANSWER”]?:12:13)
exten => s,12,Followme(7087771111)
exten => s,13,voicemail(7087771111)
exten => s,14,Hangup

exten => i,1,Playback(invalid)
exten => i,2,goto(residential,s,4)
exten => h,1,Hangup
exten => t,1,Hangup

When incoming calls comes all 4 ext ring at the same time.
When incoming calls hangs up SIP and SCCP channels send disconnect.
In case of IAX2 the IAXY device stops ringing but it takes extra 10-15 sec. The softphone ZOIPER rings forever.
Is the IAX channel broken?

i am running