Hi Phil,
The questions on your last post are a bit more intricate to explain through this medium, but I will attempt to help.
First thing, the distortion you hear when pluging in the two jacks from the Korg is most likely due to the levels being set too high on your interface’s inputs. To avoid this, make sure you lower the input levels coming into your audio interface until the signal peaks somewhere between -12dB FS and -9dB FS (You could even go up to -6dB FS if the signal is very compressed, like in the case of distorted electric guitars and some synth patches). Then there’s the levels you set during the Mixing and, finally, Mastering stage. For more info on this subject, check out the following videos:
Another factor that affects the quality of the recorded signal could be due to input signal levels. The short answer is that you’ll need to make sure that you are using the correct cables and connections between the Korg and your interface, and that each device is set up properly to transmit and receive the correct signal level. For more info on this topic check out this article:
Another read on the subject that might be helpful:
Like I said, these are very intricate subjects which you will want to research further on your own. Hopefully, these videos and articles will help shed some light on the subject of recording audio.
Take care!