This is helpful, thank you! I've been doing exactly this and here's what I've found thus far:

1. The audio buzz goes away when I have just the apollo twin connected to my computer.
2. If i plug either of my two monitors into my computer as well the buzzing starts:
   1. When I have just the apollo twin connected and I try to plug in my Ultrafine display, as soon as the display powers on, the buzzing starts. (the ultrafine display also charges my computer, so I assume as soon as it starts charging, it adds interference)
   2. When I have just the apollo connected and I plug in my secondary monitor the buzzing starts. I don't even have to fully plug in the monitor either. As soon as the cable of the monitor touches the USB-C port on my macbook, the buzzing starts.

I am not too sure how to proceed. I've looked into getting a hum reducer, but its quite expensive and honestly at that price, I'd rather just look into higher end speakers with TRS inputs that wont cause any noise.

I found another post that suggested a box such as the below linked isolator box. The the commentor didn't give a specific brand of choice however. Any recommendations?

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https://www.amazon.com/ART-DTI-Transformer-Isolator-Eliminator/dp/B0009GUOQA/ref=sr_1_4?adgrpid=1341405740510442&hvadid=83838097795129&hvbmt=be&hvdev=c&hvlocphy=55196&hvnetw=o&hvqmt=e&hvtargid=kwd-83838822169372%3Aloc-190&hydadcr=5027_13156527&keywords=audio+transformer+isolation&qid=1679769826&sr=8-4