PWM on fan controller, could be it.
note: I'am very noisy sensitive, especially to syncronous aka fan noise.
did built a few low noise cases,.. and also noticed, that in the below 1500rpm, when the fan controller is using pwm, aka pulse , and transferse the noise as a little jolt . the motor circuit , can have a little whine. there are only a few good fans that, do not have it pronounced. this would need to be hacked. as there is no remedy software wise.
in the past monitors had buzzing too.
if possible, up the fan speed, till the buzz is reduced , and live with higher airflow noise level .
note: thinking of buying a mac studio, but with this noise, it's a issue for me.
note: I'am very noisy sensitive, especially to syncronous aka fan noise.
did built a few low noise cases,.. and also noticed, that in the below 1500rpm, when the fan controller is using pwm, aka pulse , and transferse the noise as a little jolt . the motor circuit , can have a little whine. there are only a few good fans that, do not have it pronounced. this would need to be hacked. as there is no remedy software wise.
in the past monitors had buzzing too.
if possible, up the fan speed, till the buzz is reduced , and live with higher airflow noise level .
note: thinking of buying a mac studio, but with this noise, it's a issue for me.