You’ve plugged in your EverCharge pad, placed your Buddy tVNS on top, and then you hear it — a faint, slightly alien sound. Not quite a buzz, not quite a hum. Something more like a tiny dial-up modem trying to connect to the internet in 1997.
You’re not imagining it, and nothing is broken. That sound is actually your charger and your Buddy tVNS talking to each other.
Wait, they’re talking?
Sort of, yes. Wireless charging isn’t just about dumping energy from one coil to another. The charging pad and the device need to agree on things first. How much power to send. Whether the alignment is good. How full the battery is. Whether to speed up, slow down, or stop. All of this happens through a conversation carried on the magnetic field itself — the pad modulates its power signal, and the device responds. Back and forth, hundreds of times a second.
Those rapid exchanges are what you’re hearing. The coils and components vibrate very slightly at certain frequencies as the signal modulates, and some of those vibrations land in the range your ears can pick up. The result is that distinctive warbling, chirping sound — the audible side-effect of a negotiation happening in magnetic code.
Why does it change?
If you listen closely, you’ll notice the sound isn’t constant. It shifts in pitch and pattern. That’s because the conversation changes depending on what’s happening. Early on, the charger and Buddy are figuring each other out — checking alignment, agreeing on power levels. As the battery fills up, the tone of the conversation changes. Near the end of a charge, things get quieter as the charger dials back and the exchanges become less frequent. It’s a bit like two people wrapping up a phone call — shorter replies, longer pauses.
Is it a problem?
Not at all. The sound is a normal part of how wireless charging works. You’ll hear the same thing from phone wireless chargers and electric toothbrush docks if you listen carefully enough — the Buddy’s EverCharge pad just happens to be a particularly chatty conversationalist.
If the sound bothers you, make sure Buddy tVNS is centred on the pad. Better alignment means a smoother conversation and often a quieter one. But there’s nothing to worry about — your charger is just doing its job, and now you know exactly what it’s saying.
The nerdy bit (for those who want it)
The technical name for what’s happening is magnetostriction — the physical expansion and contraction of the ferrite materials in the coil as the magnetic field oscillates. There’s also a contribution from Lorentz forces on the coil windings themselves, and from tiny ceramic capacitors in the power circuit that physically flex under voltage changes. When any of these vibrations hit frequencies between about 20 Hz and 20 kHz, you hear them. The modulation protocol that carries the charger-device communication creates patterns right in that audible sweet spot, which is why wireless chargers sound the way they do.
So next time you hear that little warble, don’t reach for the warranty card. Just know your charger and your Buddy are having a perfectly normal chat about how best to look after you.