Out of the box, the highs are sibilant, but that can be adjusted using the equalizer tool in the Soundcore app.
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I personally got even more when I listened at a moderate volume and made only a few phone calls under 10 minutes each.
The case, the case is horrible, cheap plastic, probably wouldn't survive a fall from more than 8 feet, I haven't tried it but I have no trust in the claim these are water proof if anyone has recommendations for new headphones please leave them here.