Audio stream stripped from MOV file

Shotstack API
1

In testing the API for our needs, passing a file uploaded from an iPhone loses its audio. The clip>asset includes "volume": 1 so this doesn’t seem to be a settings issue. When passing this file through probe, it includes the audio stream. However, after sending to Shotstack and passing the result through probe, video has no audio stream.

Here is an example of our sent schema:

{
    "timeline": {
        "tracks": [
            {
                "clips": [
                    {
                        "asset": {
                            "type": "video",
                            "src": "", // MOV File
                            "volume": 1
                        },
                        "start": 0,
                        "length": 7
                    }
                ]
            }
        ]
    },
    "output": {
        "format": "mp4",
        "size": {
            "width": 1080,
            "height": 1920
        },
        "mute": false,
        "thumbnail": {
            "capture": 1,
            "scale": 1
        }
    }
}

We don’t manipulate the videos prior to attempting to upload the files, so they are using standard AAC codec for the audio. Please let me know how I can ensure the audio comes through as expected.

2

After a great deal of tinkering, it appears the issue is with mute: false. This attribute seems to mute the output regardless of being set to true or false.