I have no clue what to change to fix the following problem:
I have an IAX2 configuration.
An external call goes to an Extension and then to the Follow Me setting.
If I call the extension the Telco/Carrier says the line is busy.
But if I call the same number only seconds (or sometimes two/three times) later it goes through and the caller can listen the ringing-tone or better MOH (because of “tr” as dial command option).
The IAX channels/Trunks are registered (at least I can see that they are not disrupted).
1.2.3.4:4569 N abcdef 4.3.2.1:4569 60 Registered
xx_outbound/abcdef 1.2.3.4 (S) 255.255.255.255 4569 OK (33 ms)
The IAX Registration Times are: minregexpire 60, maxregexpire 3600.
The context parameters are:
qualify=yes
disallow=all
permit=1.2.3.4/255.255.255.0
deny=0.0.0.0/0.0.0.0
allow=alaw&g729&gsm
context=from-trunk
Which IAX2 setting I should change to avoid this problem?