SP w/ Apollo twin, sample quality and in/outs

[Heddy]

I'm getting ready for a show & sampling some full beats from Wav files on my computer onto pads. Once sampled in as loops, the beats seem to lose quality.

I'm using a balanced quarter inch output from the Apollo, to the RCA inputs on the SP. I've tried with the Stereo button lit and unlit and either way the beat doesn't bump as much/ is a little muddy.

Also, when playing back into the speakers through the Apollo, the samples are only playing on the left side of the stereo input. The apollo twin only has one input so I don't know if it's cuz it's not 2 stereo inputs? When hearing the loops from headphones directly from the SP they still sound janky, but want to also be able to check in speakers adequately.

Any suggestions would help!