What have you got the RCAs plugged into in the amp? Phono In or Line In?
I’m guessing Phono In, because Phono In has pre-amplification to boost the sound from turntables, which will cause distortion from a digital source like your controller.
Pretty sure if you switch to a Line In RCA input, your problems will be solved.
And if I’m wrong, then sorry, can’t help beyind what DJ Vintage said, above 🙂
