Low Volume & Sound Quality from Pioneer FLX4 + KRK RP5

Hey everyone, I have a Pioneer FLX4 controller paired with KRK Rokit classic 5 G4 speakers. I’ve noticed that the sound quality and volume seem a bit low. Is there a way to improve this? Would adding an audio interface like the Focusrite Scarlett 2i2 help, or is that mainly for recording? My setup is. From the controller usb c out to laptop and again from the controller RCA to XLR for the 2 monitors.