Buzzing power supply? AR and A4 MK1

yesterday I had a chance to connect my AR and A4 MK1 to a PA speakers - so far so good.
I realized that from A4 and AR using the original power supply I will have a buzz (drone-like) sound in the background through the speakers…
the sound is also there when both units are not powered ON - so buzz through speakers is there even they are powered OFF!

disconnected AR and A4 from power circuit and using my power banks (®-XT-20000QC2-Powerbank-moderner-20400mAh/dp/B01M9BGFJM) and the buzz-drone is gone…

I also have tried different wall plugs and that stuff - we also have different gear connected (Digitakt, RC 505, Traktor S4) but the problem seems to be the power supplies of AR and A4 mk1.

has anyone noticed similar issues/behaviour?

Not really no. How is your cabling hygiene? is there any chance that the power supply cables are touching / near your audio cables?

If power cables and audio cables must pass, it is often recommended that they do so at a 90 degree angle.

Also make sure the power supplies themselves are not touching any cables

1 Like

I put my cables in the washing machine every week! :crazy_face:

I am aware not to cross / touch power and audio cables. power supply cables were also fine.

also was thinking of a ground problem but why all other devices were not affected by?