Calls interrupted in iOS when receiving incoming in-app notifications or when the screen saver is on

[mbedial]

Hi,
we are receiving complaints from our customers since they are having some failures during a live call from iOS to a normal phone (we use WCS as webrtc/SIP gateway).
To be exact, the call is estalished but when the user receives an incoming inapp notifciation (e.g whatsapp) the call is silenced for a few seconds. This also happens if the user switchs off the screen of the mobile in order to avoid to touch any icon of the screen.
Is there any fix to avoid this behaviour?

Thanks in advance.

 

[Max]

Good day.
This seems like the same problem as playback in background: then Safari browser goes to background it stops sending and playing video, but proceeds to send audio. So, client does not hear other call side, but other side still hears the client.
We raised the ticket WCS-2681 to investigate the issue and let you know result in this topic.

 

[mbedial]

Thanks for you quick answer Max.
Actually the problem isn't the safari but the iOS library since we have the issue in one app. I mean, we have developed an app that we have published in the App Store. It's just an audio app to make voice calls, we don't use video, and it seems than it doesn't send auidio either since you can't heard audio in both sides (caller and called). It happens during 5-6 seconds more or less.
We have been trying to find out if we can change anything in the library but without success.

BR
Mario

 

[Max]

Actually the problem isn't the safari but the iOS library since we have the issue in one app

Do you set this Xcode option? Also, please read this article where some background tweaks are described.

 

[mbedial]

We have the background mode: Audio, Airplay, and Picture in Picture enabled in the Capabilities, and the audio and voip as UIBackgroundModes in the info.plist, but still having the problem commented.

 

[Max]

Good day.
We investigated the issue.
According to Apple and Google Policy, camera usage is forbidden in background mode, both for browsers and native applications. There is a workaround for Android devices only.
However, microphone still can be used in iOS native applications. To do this:
1. Add background mode tweaks to Info.plist

    <key>UIBackgroundModes</key>
    <array>
        <string>audio</string>
        <string>voip</string>
    </array>

2. Set the fiollowing options in Xcode for your app target on Signing and Capabilities tab:

We tested this on TwoWayStreaming application, video publishing stops when pressing Home button, but audio still published without interraption.

 

[mbedial]

Hi again, even when we config the Xcode like this:

<key>UIBackgroundModes</key>
<array>
<string>audio</string>
<string>processing</string>
<string>remote-notification</string>
<string>voip</string>
</array>

We are still having the problem when the user press the home button or when the iphone receives a normal incoming call. The conversation is cut for a few seconds.

BR
Mario

 

[Max]

Good day.
Please try to enable Background fetch in addition to already enabled Xcode switches
We tried to reproduce the issue in PhoneMin example (audio only WebRTC-SIP calls), and conversation is not intrerrupted while application goes to background.