Playing Karaoke on a projector w/ iPad4

We are using the app Karaoke Anywhere HD to try and play Karaoke on our iPd 4 using a projector and a sound system.

We connect the iPad using a lightning adapter to the projecter and the video works just fine. We can also attache a sound system to the iPad using the 3.5mm jack and it works just fine. However, we can't make both work at the same time.

Any ideas what we need to get both to work at the same time. We do have a separate system for the singing mic, so we're good there. Just need to get the video and song to play at the same time.

Any ideas why they don't both play together?