Internal calls to voicemail not ending when phone is hung up

[kaiserh]

I have a client using an on-prem 3CX with half a dozen handsets across two offices.
The 3CX system is installed at Office A.
They have a staff member at Office B that answers most of their incoming calls. She is in a ring group with a couple of other handsets in the same office.
What's happening is that when she calls the main extension at Office A (via, say, calling extension 100), and leaves a message on voicemail, occasionally the call is not ended when she hangs up the phone.
This then means that 3CX thinks she's on the phone, and incoming calls skip her phone and ring on the other handsets.

Does anyone know what could be causing the call voicemail to not end when she hangs up the phone?

 

[TheodorosG_3CX]

In Office B are you using ip phones or 3CX Clients?

 

[kaiserh]

In Office B are you using ip phones or 3CX Clients?

We're using IP phones at both office A and B.
The call being made to voicemail from Office A to B is made on an IP phone.

 

[TheodorosG_3CX]

How is the phone provisioned? Are you using an SBC?

 

[kaiserh]

No, no SBC - initially at Site B there was to be just one phone. They now have three Yealink T43U IP phones.

 

[TheodorosG_3CX]

If you are using STUN this can explain the issue.
This model though can be a router phone, why not provision with this supported method and try again?

 

[kaiserh]

When Site B was initially deployed, router phones were not a thing.
How can I upgrade one of these IP phones to be a router phone?

From reading the docs, it seems that the first phone deployed at a remote site, if it is a supported model, will automatically become a router phone. I can't find any info on how to make an existing deployment of phones change over so that one phone is a router phone and the other phones are connecting via the router phone.

 

[SteveITS]

It’s not automatic, just required, in that STUN isn’t supported.

Delete the phone and re-add it as a router/direct connect phone. Reset or reboot it to reprovision. Save the phone web page password before deleting it.

 

[kaiserh]

Do you know how to specifically make a phone a router phone.
There's no information in the manual on how to do this, just that you need to have one.
https://www.3cx.com/docs/manual/ip-phones/

 

[SteveITS]

From https://www.3cx.com/sip-phones/ find the phone model:
https://www.3cx.com/sip-phones/yealink-t4-series/#h.wmsoriilsyve
"connect directly" = router phone.

 

[kaiserh]

Cool, thanks.

 

[TheodorosG_3CX]

You need to ensure first that you are on the latest supported firmware version and the proceed with the configuration guide to add the phone as router phone.
Let us know the outcome.

 

[kaiserh]

Just to confirm - if I factory reset the phone and make sure it has the latest firmware on it, then I add it in and configure it to connect directly.
Then, with the other phones at that site (another 2-3) I also need to factory reset them and configure them to connect via SBC / Router Phone?

 

[TheodorosG_3CX]

Just to confirm - if I factory reset the phone and make sure it has the latest firmware on it, then I add it in and configure it to connect directly.

That is correct.

Then, with the other phones at that site (another 2-3) I also need to factory reset them and configure them to connect via SBC / Router Phone?

This depends on how you want to proceed.
If those phones are also router phones you can add them individual or provision behind one. The suggestion is that each phone is assigned as router phone as there is no limitation.

 

[kaiserh]

OK, so simply factory reset each phone and then configure it to connect directly.
Thanks, I'll give it a go and report back.

 

[TheodorosG_3CX]

Correct. Let us know the outcome.