J-Lo and her allegedly not singing on her tracks (Sometimes)

It appears some of J-Lo's tracks are basically songs with demo singers pretty much sing much of the track.  A lot of these songs came out during J-Lo heyday of making movies.  I like J-Lo's music for its sheer poppy sounds and I think her songs are catchier the Taylor Swift’s music.  It appears other female vocalist filled out her most popular tracks.  Allegedly...

This is a practice that happens a lot.  Anyway, check out the video above.