My sample slide has movies of 2 cardiograms (heart surgery movies). The 1st plays automatic and the 2nd starts after it finishes – which is the typical animation setup I have seen on hundreds of medical slides.

To make both movies play simultaneously:

1. Select the 2nd movie

2. Change AFTER PREVIOUS to WITH PREVIOUS

3. Open the Animation Pane and verify video are set in needed animation sequence

– Troy @ TLC