Calls Immediately Drop

[DCB]

Customer has Yealinks; A T31P and a W60B with a W56H. This is hosted in AWS and the SBC is running on Raspberry PI.
Randomly (more often than not) calls are dropped as soon as someone answers. That is to say, as soon as the handset is lifted off the T31 or the button pressed on the 56H; Doesn't even make it to the person's ear.
The caller can call back right away and the call connects just fine.

Apparently this has been going on for quite a while but recently it's gotten really bad.

I'm going on-site tomorrow morning. I'm hoping any late night folks will have a simple answer.

 

[SteveITS]

Does the 3CX firewall test pass?

There’s a call quality monitoring feature in v20 that might help.

 

[DCB]

It does. I'm onsite now. We are using Bandwidth.com for trunks. I ended up switching the IPs for the registrar server and outbound proxy. That seems to have fixed the issue.

If I create a realm in Bandwidth.com and use the realm name instead of IP addresses, will that work in 3CX?
Let me know if I should start a different thread for this question. I don't post on forums a lot so I'm not sure what proper etiquette is.

 

[Alejandro_3CX]

It does. I'm onsite now. We are using Bandwidth.com for trunks. I ended up switching the IPs for the registrar server and outbound proxy. That seems to have fixed the issue.

If I create a realm in Bandwidth.com and use the realm name instead of IP addresses, will that work in 3CX?
Let me know if I should start a different thread for this question. I don't post on forums a lot so I'm not sure what proper etiquette is.

in the 3cx sip trunks you can use IPs or domains, it will work, no problem with that.

Bandwidth normally assigns you a pair of IP addresses, these are the one you need to use under “General” -> “Registrar /Server”. and under “Options” -> “Alternative Proxy”.

If they are changing these IPs, then ask them to provide you a domain so you dont have to update this in the sip trunk everytime.

 

[DCB]

It's not that they are changing their IPs. I had IP A put in as the Registrat/Server and IP B as the Alternative. When I switch them (IP B is now Registrat and A is now Alternative) that solved the problem.

Either way, glad to know domains will work. I'll get those setup with Bandwidth and make that SOP on new builds.