Incall can't hear us

[xav78]

Hello,
I try to post here as we have since last week a problem with our 3CX system V10. Whenever someone call, we can hear him but he can't. When we call him back, he can now hear us and we can hear him too. I thought it was coming from our VOIP providezr but when I tried a direct link with it, both way worked.
Any ideas why all a suddent we can have this?

 

[mixig]

Is your 3cx behind the NAT? if yes start firewall checker

 

[xav78]

yes, it is, and when I did start the firewall checker, I had all passed.
Interesting to note : we have 2 voip provider, one main, one secondary. The secondary one is working both way, if I call the number, I can hear, and I can talk.
Only the other provide got the error when receiving call, people cant' hear us. I tried so this voip provider without 3CX ( used a sip phone and create the account without 3CX ) both way works.
So I have only left the fact that when receive a call on one provider, we can hear them, but not them. When call back, both way work.
interesting