When I create a StereoPannerNode and pan it to anything less than 0, the audio is very distorted. This happens in both Chrome and Safari on my Mac running Ventura 13.2.1.

The problem is identical if I do new StereoPannerNode() or audioContext.createStereoPanner(), and is identical whether I use a mono or stereo version of the same audio sample. It is also identical wherever I place the stereo panner node in the audio chain. 

When I play the audio sample using the OS (right-click from finder and preview), changing the OS pan setting, there is no distortion. 

Here's a bit of code: 

function playSound(name, volume=1, pan=0, octave=0) {
    const buffer = loadedAudio[name]; 
    if (!buffer) {
        console.warn('sound buffer not loaded for '+name); 
        return; 
    }
    if (audioCtx.state === 'suspended') {
        return; 
    }
    const source = audioCtx.createBufferSource();
    const gainNode = audioCtx.createGain(); 
    // const panNode = new StereoPannerNode(audioCtx, {pan: pan}); 
    const panNode = audioCtx.createStereoPanner();
    source.buffer = buffer;
    const note = Math.floor(Math.random() * NOTES.length); 
    const pitch = Math.pow(2, octave) * NOTES[note];
    source.playbackRate.value = pitch; 
    panNode.pan.value = pan;
    gainNode.gain.value = volume; 
    source.connect(gainNode);
    gainNode.connect(panNode); 
    panNode.connect(audioCtx.destination); 
    source.start(0);
}