MediaPlayer on iOS stops when playing other sounds

SyntaX

I recently upgraded my project to Qt6.2 and encountered the following problem:

I am using 3 different QML Mediaplayers in my scene, one for background music and two for sound effects:

MediaPlayer {
    id: playAudioFile1
    audioOutput: AudioOutput {}

    onErrorOccurred: function (error, errorString) {
        console.info("play AudioPlayer1: Error " + error + ", as string: " + errorString)
    }

    onPlaybackStateChanged: console.log("play AudioPlayer1 playbackState changed to: " + playbackState)
}

MediaPlayer {
   id: playAudioFile2
    audioOutput: AudioOutput {}
        
    onErrorOccurred: function (error, errorString) {
        console.info("play AudioPlayer2: Error " + error + ", as string: " + errorString)
    }

    onPlaybackStateChanged: console.log("play AudioPlayer2 playbackState changed to: " + playbackState)
}

function playSound(soundFile, playerNo = 1, volume = 1.0) {

    if (soundFile !== "") {

        var playerToUse = (playerNo === 2) ? playAudioFile2 : playAudioFile1
        console.log("play Sound called for " + soundFile + " on Player" + playerNo + " with status: " + playerToUse.playbackState + " and current source: " + playerToUse.source)         
        if (playerToUse.playbackState !== MediaPlayer.PlayingState) {
           let source = "qrc:/assets/sounds/" + soundFile + ".wav"
           if (playerToUse.source != source) {
                console.log("loading new source...")
                playerToUse.source = source
           }
            
            playerToUse.play()
            console.log("play Sound: SoundEffect" + playerNo + ": Playing '" + soundFile)
        }
        else {
            console.log("play Sound: SoundEffect" + playerNo + ": Double playing prevented: '" + soundFile)
            if (playerNo === 1) {
                console.log("play Sound using player2!")
                playSound(soundFile, 2, volume)
            }
        }
    }
}

MediaPlayer {

    id: themeSong
    source: "qrc:/assets/sounds/theme.mp3"
    loops: SoundEffect.Infinite
    audioOutput: AudioOutput {}
        
    onErrorOccurred: function (error, errorString) {
        console.info("themeSong: Error " + error + ", as string: " + errorString)
    }
}

function playTheme(start) {

    if (start) {
        console.log("start playing theme")
        themeSong.play()
    }
    else {
        console.log("stop playing theme")
        themeSong.stop()
   }
}

This works seamlessly for my Android and MacOS builds, but has a strange behaviour if I am building for iOS/iPad:

themeSong is playing in a loop
if playing a sound, that is already set as source in a MediaPlayer, themeSong continue playing
but if a new source is set, the themeSong just stops playing, no error occurs, neither does the playbackState change nor the mediaStatus

Am I doing something completely wrong here?
Is it intended to use an own MediaPlayer for each different source so that changing it during runtime is not necessary?