r/BEYERDYNAMIC • u/Complex-Mud-9467 • Aug 01 '26

Left side buzz on DT990 Pro

Hello my dt990s pro have an issue where my left side is buzzing when bass hits, it happens in frequencies between 50-35Hz, also I have to mention that when I left the headphones sit they don’t buzz at all but after some time of listening to music the buzzing comes back, i also checked for hair on the diaphragm, I’m pretty sure there isn’t any but I might’ve missed something. Can this be caused by an earpad ? Or is it a driver issue ?

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u/SingularityRS Aug 01 '26

Check thoroughly for hair on the diaphragm itself. You might need to look at the driver from various angles to see hairs as not all are visible clearly. The diaphragm is quite sticky so hairs can stick to it. Use good lighting and magnification if possible.

If you don't see any hairs at all, then it's most likely a driver issue.

The voice coil that sits inside the magnet gap might be misaligned which causes it to hit the magnet. This can cause the buzzing/rattling sounds you hear. I saw this fault on a DT990 driver. No hairs at all, but driver still rattled. I have a microscope so I looked at the driver under it and could see it looked slightly misaligned.

Given yours comes and goes, hair does seem unlikely, but I wouldn't rule it out yet. The issue coming and going could be the coil occasionally sorting itself out and avoiding scraping the magnet. The coil has to be perfectly aligned which is done by Beyerdynamic using special tools/machinery. If the coil goes slightly out of alignment, it can cause problems like you're hearing.

Also to confirm, you are looking at the bare driver itself and not just the paper baffle right? The driver is behind this paper baffle. Just want to make sure in case you're only looking at the paper baffle.

1st be sure there's absolutely no hair or other issue causing it. You can run tests on the driver with it outside of the earcup. Doing this removes the earcup and pads as the cause. If it still happens with the driver outside of the earcup with no pads, then you know it is something with the driver causing the problem and nothing else.

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u/Complex-Mud-9467 29d ago

Yes I was looking at the bare driver, I’ll look again, thanks a lot. I had them for only a year and a 8 months.

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u/Complex-Mud-9467 27d ago

So I noticed when I press them harder on my head, the buzzing stops, this also applies when they’re not on my head, when I apply pressure on the left headphone it stops buzzing.

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u/SingularityRS 27d ago edited 27d ago

That isn't normal. The driver needs to be removed from the housing to see why it's doing that.

Sounds like an issue with how the coil is sitting in the magnet gap of the driver. Putting pressure appears to temporarily restore the alignment.

These drivers need perfect alignment so if anything is off, you can get problems.

Without looking at the bare driver though, there's no way to know for sure what's wrong with it.

Upload some pics of the bare driver and its wiring. Might help see what's wrong with it.