A boomy sound in your headphones is a bit like your neighbour's subwoofer through the wall – nobody asked for it, but there it goes rumbling away. Luckily with the VMK20, the cause is usually simple and the fix is quicker than a kebab shop queue.
Why do the headphones sound boomy?
The number one culprit by a landslide is ANC, aka active noise cancelling. The VMK20's noise cancelling function is separate from the Bluetooth connection, which means one important thing: ANC doesn't turn off automatically with the headphones. It stays on even if you power the headphones off and back on again.
When ANC is on, it actively generates counter-sound to cancel ambient noise. In a quiet room, this comes through as a faint hiss or whoosh – that's completely normal. But if the ear cushions aren't sealing properly, ANC starts compensating for the leaking sound and the result is that familiar boominess. Bass bloats, mids get muddy, and the whole thing sounds like you're listening to music from the bottom of a bucket.
The other common cause is simply worn-out ear cushions. After five years, the internal foam softens and the seal weakens. It affects the sound more than you'd think – especially the bass.
How to fix it
- Check the ANC status. Look at the left ear cup. If the green LED is lit, ANC is on. Press the ANC button once – the LED turns off and noise cancelling is disabled.
- Restart the headphones. Power off using the MFB button (the middle one on the right side), wait a couple of seconds, and power back on.
- Do a reset. Plug a 3.5mm AUX cable into the headphones and unplug it. This cuts the Bluetooth circuit connection and resets the settings. Simple as.
- Listen without ANC. Put on your favourite track and compare the sound with ANC on and off. If it sounds good without ANC but boomy with it, the problem is the seal.
- Check the ear cushions. Press the ear cups gently against your ears. If the seal feels loose or the cushions are visibly flattened, it's time to swap them out. The old cushions twist off and the new ones snap right into place.
If you've been using the headphones for several years, replacing the ear cushions is probably the move. New cushions restore both the seal and the sound quality surprisingly close to the original.
If nothing helps
If you've tried everything above and the boominess won't budge, it might be a driver or ANC circuit fault. That's a job for the repair team.
- Snap a photo of the headphones and the condition of the ear cushions
- Dig up your order number
- Send both to info@valco.fi
Our service team in Kajaani will sort it out. We don't throw headphones in the bin around here – that's the whole point.
And if your headphones are past the warranty period but otherwise in good nick, the repair package still costs a fraction of buying new ones. That money goes to a good cause too: the Death Star construction fund and Jasse's beer tab.
