Sometimes my active near-field monitors hum

ToneControl

The suddenly ramp up in volume as if someone turned up a volume control
They both do it at the same time, and continue unchanged if you press the mute button on each

After a while it goes away

I wonder if the mains supply is noisy, I can't see anything else in the room changing

thermionic

Teach them the words?

Winny_Pooh

CRT monitor somewhere, lights on a dimmer switch? Fridge nearby?

spark240

Winny_Pooh said:

CRT monitor somewhere, lights on a dimmer switch? Fridge nearby?

Maybe......any definitive times of the day or night ?...you had any new wi fi gadgets recently?.....turn off everything possible in the house .

mine comes from the kitchen dimmer switch...

ToneControl

spark240 said:

Winny_Pooh said:

CRT monitor somewhere, lights on a dimmer switch? Fridge nearby?

Maybe......any definitive times of the day or night ?...you had any new wi fi gadgets recently?.....turn off everything possible in the house .

mine comes from the kitchen dimmer switch...

it's been doing it a long time, none of those nearby

I may have to go round switching things off I wonder if it's the CH pump