LED display emits high-pitched noise

[Brixton]

It's a high-frequency sound which has always been present to a degree (and it depends on the size of the graphic on the display) - but now much more noticeable on the new osc 'Harm' graphic as it blinks on/off. I have my MF connected by its power supply to a secure outlet. It doesn't show up on recordings, and seems to come and go as you cycle through the menu, so just wondering if this is 'normal' noise or something that can be mitigated?

[vinark]

You don't mention what your MF is connected to and how you hear it, speakers, headphones? To me it sounds the same problem as computer noise making it into the audio path, which is a ground loop issue where fluctuations in the power needed causes this noise.
Do you also have it with just the MF powersuply and headphones and nothing else connected? If yes then it might be a defective MF, but if no noise then power suply noise making it into the audio path.
Are you using a balanced audio cable to your audio gear?

[Brixton]

Thanks for replying -- it's connected by balanced cable to mixer then audio interface to monitors. Connected to a grounded power bar. I've tried isolating it to a single outlet but the same issue...

[vinark]

Thanks for replying -- it's connected by balanced cable to mixer then audio interface to monitors. Connected to a grounded power bar. I've tried isolating it to a single outlet but the same issue...

And headphones and power adapter only, so no audio out and usb?