Solved We cannot get the 3CX app on iPhones to ring

[GenericAccount]

When you call a number or extension running the 3CX app on an iPhone, it WILL NOT ring unless you have the 3CX app open on the screen. If you exit out of it or minimize it, it refuses to ring.

Android devices running the 3CX app ring no problem whether the app is open or not.

We've just updated to the latest version on the server and the iPhone app but still no luck. Any idea what could cause this?

 

[JohnS_3CX]

Hi @Kerby

If you provision the same extension on an android or alternatively, if you simply register it in the webclient, will it ring normally or will it also stop ringing after 1.5 second?

Have them side by side when you test next time (the iPhone and the webclient) so you have a good comparison

 

[KyleKSIP]

Hi @Kerby

If you provision the same extension on an android or alternatively, if you simply register it in the webclient, will it ring normally or will it also stop ringing after 1.5 second?

Have them side by side when you test next time (the iPhone and the webclient) so you have a good comparison

On Android it works perfectly or the web client, the issue only appears to be with iOS mobile devices.... Here is a weird one. If my Android and iPhone are both registered on the mobile app at the same time the issue goes away, but if only my iPhone is registered, the issue is present.

 

[JohnS_3CX]

@Kerby

Confirm you please the following?

iPhone Model:
iOS Version:
3CX App version:
PBX Version:

 

[GenericAccount]

Is this still an issue?

Yes this is still an issue for us.

 

[GenericAccount]

Just to let everyone know, we used Wireshark to grab some packets and found that Apple's push servers were rejecting our packets because our cipher suite was too weak. We upgraded the strength of our cipher suite on our 3CX server, rebooted, and the packets were now successfully going through to Apple's servers.

The 3CX mobile app now works for our iPhone users.

 

[Mekio]

Just to let everyone know, we used Wireshark to grab some packets and found that Apple's push servers were rejecting our packets because our cipher suite was too weak. We upgraded the strength of our cipher suite on our 3CX server, rebooted, and the packets were now successfully going through to Apple's servers.

The 3CX mobile app now works for our iPhone users.

Which port are you using to correct this?

 

[JohnS_3CX]

@Mekio run your capture, make a call to an iOS extension and then end the capture.

Filter for ip.addr==17.0.0.0/8

You will see the attempt going towards apple's server at 443

If you are failing the handshake during the cipher exchange, then compare your offered ciphers VS the ones the apple server replies with to ensure you offer ones that match theirs.

 

[doubledown00]

I am seeing the exact same behavior.

Running version 16.0.619
Debian ISO running as a virtual machine on Cent OS 8.
Iphone SE, running 13.5.1
3cx app is the most recent from the App store.

 

[edfosho]

Are there any 3CX recommendations for the cipher exchanges with the Apple servers?

I have also got some users who aren't getting calls through on the new iOS app. This is an issue introduced in the new iOS app.

3CX server on Debian 9.5 stretch

 

[JohnS_3CX]

Are there any 3CX recommendations for the cipher exchanges with the Apple servers?

I have also got some users who aren't getting calls through on the new iOS app. This is an issue introduced in the new iOS app.

3CX server on Debian 9.5 stretch

This matter regarding ciphers was specifically for Windows servers, not Debian.

Ensure your PBX is on the latest stable update and check the specific users extensions. Always make a fresh extension with default settings and test it on their phone to quickly eliminate the possibility of extension misconfiguration if you want to save some time. Then depending on what you find, you can move thusly.

 

[pmv800]

We are experiencing strange APN issues as well with a couple different 3CX servers. The calls don't pick up or drop right after the pickup attempt from the Apple mobile app. Other times users hear busy tones after a pickup attempt. When using the webclient to control the mobile app to initiate a call, the first call fails at times and they start a second call attempt to the same number and the 2nd call gets conference onto the first call attempt. Yet they can't hang it up nor see the call in a conference state.

One of the servers is 3CX version 16.0.619 Enterprise on Debian 9.5 Apple iOS 13.5.1 iPhone XR

The other 3CX server 16.0.584 Professional is on a Windows 2016 with several different iPhones models.

We are going to try deleting a couple of simple extensions and recreating to if it fixes the issues. Yet we are more worried about the other complex extensions part of digital receptionists, ring groups, call queues, extension forwarding, voicemail greetings/messages, and BLFs they have or are assigned on other phones.

 

[jacobegan]

Very similar to what I posted earlier.

 

[pmv800]

@3CXsupport We tried recreatin extensions from scratch and had no luck. Any other ideas on what to look for next?

 

[JohnS_3CX]

@pmv800 you're describing an entirely different type of error. In your case, the phone rings but the call cannot be picked up. It's best to start a separate thread on this matter.

I'm closing this thread since the original poster solved their issue.