Some Apple Studio Display owners have begun complaining that their high-priced displays are making a high-pitched buzzing sound that seems to be coming from the top of the screen or behind it. It’s possible the issue is caused by electrical interference.
As reported by MacRumors, users have complained on Twitter, Reddit, and the Apple Support Community dating back to June, and more recently on the MacRumors forums, about the issue. Users describe the sound as an “electrical buzzing” and “constant ringing” that is “loud,” “high-pitched,” and “very annoying.”
Owners report that the sound is not related to a cooling fan and only occurs when a MacBook Pro or iPad is plugged into the Studio Display. Reports say the noise can vary in intensity and pitch at different times of day.
Apple Support Community member Ryan Roberts says:
“I’m experiencing a very annoying high-pitched buzzing sound with my Studio Display, I’ve spoken to others on Twitter who also have the problem and I’ve had Apple support on the case but nothing was resolved.
[…]
“It’s not the fans, it’s a distinct (and very annoying) sound that emanates from the rear area of the display, roughly where the power supply is positioned.
“I’m 90% certain the display is picking up interference from somewhere and amplifying it, maybe through the house power circuit but I can’t be sure. Someone I spoke to believes the PSU is poorly shielded but I have no idea if that’s true either.”
Some users have suggested the Apple Studio Display picks up interference from electric car chargers. A user reported tracking the source of the interference back to Lutron Caseta light dimmers that are installed in their house.
“Whenever the dimmer is turned on, the buzzing noise starts coming out from the ASD. The dimmers are not even on the same breaker as my ASD. The only thing I can think of is that the dimmers are creating electrical noise that is propagating to the electrical panel which then propagates to the ASD.
Now it’s one thing that the dimmers are creating electrical noise. But it’s another thing that only the ASD is reacting to this noise. I don’t hear this electrical noise coming out of any other thing in my house. It appears to be an issue with the ASD power supply. Whether it’s a problem with the specific display I have or the choice of components in the design of the ASD power supply, I do not know.
Some say they have attempted to remedy the issue by using electrical power filters, with no luck. Replacement units from Apple seem to be similarly affected.