Asterisk ConfBridge application – Delay in voice path

Hi All,

I am running asterisk on Linux machine and trying to use confbridge application. Please have a look at Conf files.

sip.conf

[general]
context=default
allowoverlap=no
bindport=5060
bindaddr=0.0.0.0
srvlookup=yes
disallow = all
allow=ulaw
allow=alaw
defaultexpiry=100
[5001]
type=friend
nat=yes
host=dynamic
canreinvite=no
context= conferences
disallow = all
allow=ulaw
allow=alaw
[5002]
type=friend
nat=yes
host=dynamic
canreinvite=no
context= conferences
disallow = all
allow=ulaw
allow=alaw
[5003]
type=friend
nat=yes
host=dynamic
canreinvite=no
context= conferences
disallow = all
allow=ulaw
allow=alaw
[5004]
type=friend
nat=yes
host=dynamic
canreinvite=no
context= conferences
disallow = all
allow=ulaw
allow=alaw

extensions.conf

[general]
static = yes
writeprotect = no
clearglobalvars = no
autofallthrough = yes

[conferences]
exten = 999,1,Answer()
exten = 999,n,ConfBridge(conference,M)

I have added 4 users to confbridge by dialing 999.From first 3 users [X-lite] no delay in voice path.

But 4th user [X-lite] has delay in voice path and it taking nearly 30 Seconds [ some times 1minute also] to reach voice to remaining 3-persons.

Once in a while it happening after adding 3rd user itself.

Any Idea - Please suggest me.

Thanks and Regards,
Garge.