Agreed on the use of grounds through the audio cables.... they will not safely carry the 15 or 20 amps..... actually much more than that during a hot to ground fault condition. They become heating elements pretty quickly and not fast enough to protect you.

This does NOT sound like a ground problem or a ground loop. A ground loop would have a 60hz hum.... like a guitar amp when you touch the tip of the guitar cord. It's approximately a low "B" in pitch.

You can try removing grounds with the adapters..... never cut the ground plug connector off. I doubt that you will solve the whine this way.

Whining sounds are mostly caused by interference. In another forum site, we get this kind of issue from folks using the wireless mice and other radio frequency devices around the audio gear.

You absolutely must find the source of the noise first before you can work on solving it.

Since many folks use unbalanced wiring and cheap cords, the first step here is to ID the offending device. Shut off the wireless devices (one at a time, but then leave them off if there are multiple devices... perhaps the source is not singular but from multiple sources) that are in use in the proximity to the computer/DAW. Did it go away?

Don't rule out the wi-fi gear nearby either. Turn off the wi-fi internet.

Shut down other computers as well.

Unplug the wires from the inputs to the speakers and with them turned on and up and nothing connected, do you still hear it?

Unplug any outboard gear from the system. Gone?

Leave no stone unturned in the search for this problem.

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