Transfer call to own extension doesn't work with deskphone

[sseidel]

Hi,

we have a self-hosted 3CX with two SBCs at the branch offices. I have a user that has a deskphone (Fanvil X4G) and a DECT headset (Jabra) connected to a Gigaset N510. Everything work fine with this setup, except for moving calls from the deskphone to the headset. For regular outbound dialling the user can use the Windows client, although Wine on the Linux developer machine has some graphical glitches. But when the user needs to call a number and make DTMF input, ideally the call should start on the deskphone, DTMF input made and then transferred to the headset (same extension). But, whenever the call is transferred, the Fanvil just says "Failed". Now, I thought this is just something that is not supported (even though user here have reported it to work) until the user tried with the 3CX Android app. This works perfectly: call is started on the Android app, then a transfer is made to the same extension, headset rings and call is on the headset. Why does that not work with the deskphone?

Thanks,

Stefan

 

[JohnS_3CX]

Hi Stefan,

You also have the ability to use the Web Client so you don't have to rely on WINE (just use chrome for linux to access yourfqdn.3cx.com:5001).

The Jabra DECT is not officially supported for use on the N510 so I don't know what behavior to expect there, you can see the handsets that can be paired with the N510 here: https://www.3cx.com/sip-phones/gigaset-n510/

That being said though, have you checked your extension settings for the specific user yet? See if "PBX Delivers Audio" can help. This might be the reason it works via the Android client transfer VS the Fanvil transfer

 

[sseidel]

Web Client doesn't do MakeCall, which is required for the N510 (NB this is not specific to the Jabra headset, any DECT phone would behave the same, but the specialty for the headset is that it cannot dial DTMF for obvious reasons). Exactly why MakeCall is not supported in the Web Client I don't understand.

Are there any DECT headsets that are officially supported?

I tried "PBX delivers Audio" and it didn't seem to make a difference.

But I found out that it was something entirely different: apparently it's only blind transfer that doesn't work, and the UX for regular transfers is very strange. So it works now like this: user dials outside number, dials DTMF. Then does "XFER", dials own number, does not hit "XFER", but "Dial". Then picks up at the headset. Then does not hang up at the deskphone (doing so will result in the call being held) but rather now hits the "XFER" key again, and finally, the call is on the headset. Quite disturbing, honestly.

 

[JohnS_3CX]

I don't understand exactly what you mean, you can call using the webclient (including any DTMF), and then transfer said call to yourself.

If your extension has accept multiple calls then the Jabra DECT headset will ring and you can pick up from there and continue your call.


NB: As for headsets, DECT is not necessary, you can just get a wireless headset like Sennheiser or Jabra and connect it straight to the webclient via Chrome. You won't need a Fanvil or Desktop Client either, as the webclient is standalone and OS independent.

 

[sseidel]

Well, the Fanvil phone is company standard, the DECT headset is especially for this user and the workstation doesn't support local audio, that's why calling from the web client does not work.

Also, there's a stark difference between DECT and other wireless headset in reliability and range, but you probably know that.

And again, the web client does only do half the job since it's not possible to use it to control non-uaCSTA devices, of which there are many.

I agree it's a niche problem, but not an unrealistic one for sure. That's why I was asking if there are officially supported DECT headsets.

 

[JohnS_3CX]

Indeed niche

There are no DECT headsets we specifically support. Also we do not support DECT under SBC (you will see this on the known limitations https://www.3cx.com/sip-phones/gigaset-n510/#h.e9jcoksdu2ik )

You can make it work of course (as you already have) by manually setting it up but it is not a 3CX supported scenario, we cannot guarantee it will operate correctly under these conditions.

I don't know if you will have better luck using a VPN to connect that site to the PBX, might be worth a shot if it can be done without upsetting your network configuration. At least in this mode the DECT will appear local and operate under a supported scenario, so your forwards using the fanvil might have a better chance to be successful.

 

[sseidel]

Indeed niche

There are no DECT headsets we specifically support. Also we do not support DECT under SBC (you will see this on the known limitations https://www.3cx.com/sip-phones/gigaset-n510/#h.e9jcoksdu2ik )

You can make it work of course (as you already have) by manually setting it up but it is not a 3CX supported scenario, we cannot guarantee it will operate correctly under these conditions.

I don't know if you will have better luck using a VPN to connect that site to the PBX, might be worth a shot if it can be done without upsetting your network configuration. At least in this mode the DECT will appear local and operate under a supported scenario, so your forwards using the fanvil might have a better chance to be successful.

Ah, sorry forgot to mention that's what we do. So we use SBC for the supported phones (Fanvil) and VPN for the only locally supported like N510 and Grandstream HT801/2.

 

[JohnS_3CX]

The SBC is more of a useful tool for NAT traversal.

If you already have your VPN setup between your PBX and the phones site, your devices should all appear as local. In this case I don't think you will get any additional benefit by running an SBC since you don't really need NAT traversal in this scenario.

How about reprovisioning the Fanvil as a local phone in this case?