Faced with one way audio issue

[Knight!]

Good day Team,

I faced with issue like description here - https://www.3cx.com/community/threads/random-one-way-audio.75601/
but have different with Description in another topic

Two or three extensions has issue like one way audio ( only by using 3CX mobile Apps ) for same users Window 3CX Application work perfectly , but other working without a problem ( 3CX Mobile and 3CX Windows Client ) in different connection options

Could you please support me and give a settings advice i need to recheck for 3CX Windows V20 Server for issued ext . ?

I try to reset Ext are not working and re-provision them with Server ( Not help )
I try to delete Ext and Re-create it from zero for be shure all setting for account set as default ( not helped )
I try to set PBX delivers Audio ( not helped )
Try turn off SRTP for them

But unfortunately it doesn't help

Also i start to think about a mobile hardware version/model doesn't support V20 ( on V18 after setup UDP/RTP all starts to work without any voice issues )
FW setup is correct ( because other clients with mobile 3CX Apps can connect and talk without any issues ) on 18 and on 20 Verion of server .

 

[Alphabetic]

Hello

first thing you need to establish is that your 3CX firewall checker passes.

 

[Knight!]

Hello

first thing you need to establish is that your 3CX firewall checker passes.

Could you please tell me ( if know ) , for pass a FW checker, which host does the Server connect to check port access?

 

[Alphabetic]

So your reply makes me suspicious that your firewall is too restrictive. Fix this, get the firewall check to pass and you'll be sorted.