Created Playlist changes source of some mp3-tracks to spotify

I created a new playlist. All of the songs that I add to this, have an mp3 as source on my mac - although every 5-10 songs Djay Pro 2 changes the source to spotify in that playlist! I want to create playlist only based on my mp3-collection that I have on my mac without relying on spotify… Any ideas how to fix this?! Thx!