No sound

I am new to iPad, animoog was one of the first apps I got. It must be too awesome to be true, because now I can’t get any sound out of it. The keys are not lighting up like they did at first when it was making awesome sound. I have sounds on other apps. I tried to reset everything, still no dice. Mayday!

Thanks in advance

Okay I got some sound back, but not all. All keys sound in mono mode, but only some sound in poly mode. I tried the hardware slide switch, and the “use slide switch to: lock rotation setting”. What to try next.