Very strange why this is happening! Could you let me know what version of iOS you have on your iPad? And do you have other apps running in the background while you're playing?
Could you also try muting the sound in the game the next time you start it up, and then trying to play and see if the problem still happens when the sound has been muted? We haven't been able to duplicate this problem ourselves, so we're still trying to figure out what exactly would be causing it for you.
My IPad is on IOS 12.1, and I don’t have that much apps running in the background.