When I have an active loop on deck 1 and a song playing on deck 2, weird things happen when I use Neural Mix stuff in the middle of the loop. When the loop reaches the beginning again, the sound is audibly out of sync. It takes a short while to correct and then it is fine again for subsequent returns but it‘s slightly disconcerting and just sounds bad.
On older hardware, even weirder stuff happens: on my iPhone X, the playhead goes out of the loop until the neural mix effect sets in. Only then does playback return to normal.
Hardware: iPad Air (4th Generation)