Don't panic
Whatever icon you see beside songs in LW reflects which player is set as the default player for that type of file. So... somehow RP has become your default music player.

To change that, go to LW's library & click on Saved Files. Highlight a file & click Explore... your saved folder will open. Now right click on a music file within that saved folder > open with > choose program. Click on whichever music player you want to use & then tick the box to always use that program. Click ok.