Schiit USB Cable

So I just purchased a Syn and Gjallarhorn and connected it to my PC via the supplied cable from Schiit with the Syn (RIP).

I noticed a hum from the amp during intense GPU (4070) usage. So after a lot of moving, repositioning, changing outlets and so on, it ended up being the Schiit USB cable that came with the Syn.

It's now connected through optical. I'll look through the sub for any suggested replacement USB cable.

Any other tips that I need to know?