"Unable to connect to the voice call: timed out waiting for peer connection" on mobile app but working with the web version on the same device

[ngthwi]

Summary

Cannot start/join to call

On the iPad Calls doesn't work with the app despite working with Safari which confirms that ports 443,8443 TCP/UDP are correctly opened.

Environment Information

• Device Name: iPhone and iPad
• OS Version: 18.3.1
• Mattermost App Version: 2.25.1 (Build 607)
• Mattermost Server Version: 10.5 (self-hosted)
• Calls (com.mattermost.calls - 1.5.0)

Steps to reproduce

1. Open Mattermost app
2. Start call

Expected behavior

Calls started/joined successfully.

Observed behavior (that appears unintentional)

Cannot start/join the voice call. The following error appears: "Unable to connect to the voice call: timed out waiting for peer connection".

Possible fixes

No fix found.

[ngthwi]

Here's the log from the app:

2025/02/26 00:54:20:016 INFO WEBSOCKET RECONNECT MODELS BATCHING TOOK 7ms
2025/02/26 00:54:25:158 INFO Running "ChannelInfo"
2025/02/26 00:54:27:128 DEBUG calls: ws error {
    "AT_TARGET" = 2;
    "BUBBLING_PHASE" = 3;
    "CAPTURING_PHASE" = 1;
    NONE = 0;
    bubbles = 0;
    cancelBubble = 0;
    cancelable = 0;
    composed = 0;
    composedPath = "<null>";
    currentTarget = "<null>";
    defaultPrevented = 0;
    eventPhase = 0;
    initEvent = "<null>";
    isTrusted = 0;
    message = "The operation couldn\U2019t be completed. (OSStatus error -9836.)";
    preventDefault = "<null>";
    returnValue = 1;
    srcElement =     {
        CLOSED = 3;
        CLOSING = 2;
        CONNECTING = 0;
        OPEN = 1;
        "_eventEmitter" =         {
            "_nativeModule" =             {
                addListener = "<null>";
                close = "<null>";
                connect = "<null>";
                getConstants = "<null>";
                ping = "<null>";
                removeListeners = "<null>";
                send = "<null>";
                sendBinary = "<null>";
            };
        };
        "_socketId" = 0;
        "_subscriptions" =         (
        );
        addEventListener = "<null>";
        dispatchEvent = "<null>";
        onclose = "<null>";
        onerror = "<null>";
        onmessage = "<null>";
        onopen = "<null>";
        readyState = 3;
        removeEventListener = "<null>";
        url = "https://mymattermostserver/api/v4/websocket?connection_id=&sequence_number=0";
    };
    stopImmediatePropagation = "<null>";
    stopPropagation = "<null>";
    target =     {
        CLOSED = 3;
        CLOSING = 2;
        CONNECTING = 0;
        OPEN = 1;
        "_eventEmitter" =         {
            "_nativeModule" =             {
                addListener = "<null>";
                close = "<null>";
                connect = "<null>";
                getConstants = "<null>";
                ping = "<null>";
                removeListeners = "<null>";
                send = "<null>";
                sendBinary = "<null>";
            };
        };
        "_socketId" = 0;
        "_subscriptions" =         (
        );
        addEventListener = "<null>";
        dispatchEvent = "<null>";
        onclose = "<null>";
        onerror = "<null>";
        onmessage = "<null>";
        onopen = "<null>";
        readyState = 3;
        removeEventListener = "<null>";
        url = "https://mymattermostserver/api/v4/websocket?connection_id=&sequence_number=0";
    };
    timeStamp = [1740527667125](tel:1740527667125);
    type = error;
}
2025/02/26 00:54:27:128 DEBUG calls: ws close, code: 1006 reason: The operation couldn’t be completed. (OSStatus error -9836.) message: <null>
2025/02/26 00:54:28:134 DEBUG calls: attempting ws reconnection to https://mymattermostserver/api/v4/websocket
2025/02/26 00:54:28:176 DEBUG calls: ws error {
[.....]

[streamer45]

From the logs provided, it looks like it's failing to establish the initial websocket connection, which comes before any connectivity check through the UDP port.

The error reported (The operation couldn\U2019t be completed. (OSStatus error -9836.)) doesn't really ring a bell. It seems like the system isn't happy with the request for some reason. Looking further, there could be some issues with the TLS certificates.

Are you running MM on a self-signed certificate perhaps?

[ngthwi]

MM is running with a Let's Encrypt certificate.
This is from TLS Inspector: