Topic: Babyface and random crackle/popping noise

I have Babyface (the blue one) connected to an Intel NUC PC. As soon as I connect the breakout cable's XLR to my Genelecs, the speakers will start producing random noise. Like randomly popping pop corn, quite loud. Doesn't make a difference what the volume settings are. As soon as XLR is removed, the noise is gone (different noise per left and per right, left has louder noise). Headphones connected into the headphones jack (either of them) will not produce this noise.

1) What causes this kind of noise? (Back in the days a rotating hard drive might've had something to do with this type of noise, but here the noise seems totally random, I have no idea what the noise is based on.)

2) How to get rid of this noise?