Why are there no outgoing calls without incoming calls?

Question

Asterisk

The situation is as follows: a provider comes to the cisco (CISCO881-K9), leaves the cisco to the PBX (formerly Trixbox, now FreePBX) and in the absence of incoming calls (10 minutes), the ability to make outgoing calls is lost. If at this moment you make a call from a mobile phone, the call will occur normally and you will be able to call from internal phones.
The previous PBX (Trixbox means) had exactly the same problem...
hence the conclusion: it's not the PBX...
I don't know where to dig...

Answer 1

on a cat

conf t
no ip nat service sip tcp port 5060
no ip nat service sip udp port 5060