Choppy sound when using jog wheel

Hello, I just purchase a DDJ-1000 and I’m trying to get used to scratching on a DJ controller. One thing that seems to be a problem is that if I hold down the jog wheel and in effect try and play a sample or tune by spinning the wheel manually at a constant speed it doesn’t play the song as if it was playing live. The sound is choppy, almost with a constant wobble like the sampling rate on the wave file is impacting by holding down the jog wheel. It’s very annoying when trying to scratch as it just doesn’t sound smooth like a vinyl would. I imagine it is something in the settings and tried searching the forum for a similar issue but no joy. Can you please help? Thank you. Kris Gregory