Questions
Why are left and right reversed?
Check that your headphones are on the right way round, usually marked L and R. Also check the balance setting in your system sound settings.
Why is there no sound from my speakers?
Make sure the right output device is selected in your system and the browser tab isn't muted. On a phone, also turn up the media volume.
Why can't I hear high frequencies?
Many laptop and phone speakers can't play very high tones, so the result also depends on your device. Headphones usually reach higher and give a more consistent result.
Should I use headphones for the hearing test?
Yes, headphones give a more consistent result than speakers. Keep the volume low and don't turn it up to hear the highest tones.