Your headphones keep dropping the laptop. The shop tab is why.
A developer chased a maddening bug: his wireless earbuds stopped switching between laptop and phone. The culprit turned out to be an open AliExpress tab, playing a sound nobody can hear.
If you use earbuds that connect to two devices at once — phone and laptop — you know the small daily magic: a call comes in, the sound jumps over. And you know the small daily annoyance when it stops working for no reason at all.
A developer writing at blog.laserphile.com traced that annoyance to something ordinary: an AliExpress page left open in the browser. The page quietly starts the browser's audio engine, WebAudio, and pushes a tiny signal through it. You hear nothing. But your operating system sees an app playing audio, grabs the headset in high-quality music mode, and stops handing it back. The post hit the front page of Hacker News on the day we're writing this, with 225 points and 69 comments — mostly people saying they'd had the same ghost and never found it.
The sound isn't there to be heard. It's there to be measured. Every device processes audio a hair differently — the chip, the driver, the rounding in the math. Run a silent tone through it, read back the result, and you get a number that is stubbornly the same for your machine and slightly different for someone else's. That number is a fingerprint. No cookie, no login, no consent banner. Clear your cookies, open a private window, switch accounts: the audio still sounds like your laptop.
This is not new technology. Browser fingerprinting has been documented for over a decade, and the audio variant is a known trick. What is unusual here is that it left a mark you can feel with your ears.
Surveillance almost never has a symptom. This one does.
Think about how much of it you would never notice. A page reading your device's audio quirks costs nothing and shows nothing. The only reason anyone found this one is that Bluetooth multipoint — the feature that lets headphones hold two connections — happens to be fragile, and the silent tone kept the connection hostage. We don't know whether AliExpress intended the side effect, and we're not going to invent a motive. Nobody at the company has explained it publicly as far as we can see.
Anyone who bought cheap-but-decent earbuds and blames them for a bug that isn't theirs — that's most people under 40 with a laptop and a phone. Also anyone who does their shopping in a browser tab they never close: the marketplace page doesn't need you logged in to know it's you. And if you're studying anything near web development or security, notice what just happened: the thing that exposed the tracking wasn't a privacy researcher with a lab. It was one annoyed person debugging his headphones.
Two concrete things to watch. First, whether AliExpress quietly removes or changes the WebAudio call — someone will diff the page script within days, and Hacker News threads track that. Second, whether Chrome or Firefox tighten the rules: Firefox already offers audio fingerprint protection in strict mode, and the open question is whether either browser starts requiring a page to justify opening an audio context it never plays. If your multipoint suddenly starts behaving again with no update to your headphones, you'll know which side moved.
The fingerprint worked perfectly. It was the headphones that told on it. Every other site doing the same thing today is doing it without a symptom — and the only reason we're writing this is that one man wanted his earbuds to switch back to his laptop.
Sources: blog.laserphile.com (author's post, August 2026); Hacker News discussion thread #49372583 (225 points, 69 comments at time of writing).