Short answer: Turn off song/arranger mode on the slave machine.
This is how I use my OT/AK with songs:
OT is the master, set up to send program change and uses song (arranger) mode. AK is the slave, set up to receive program change and stays in PATTERN mode. The OT goes down the arranger’s list of patterns as they are programmed, and the AK changes patterns right along with it. At first I tried to use Arranger mode for both machines simultaneously, but after much effort and frustration, I figured out I didn’t need to and my problem was solved. I’m not sure if this applies to your situation. (sorry I’m tired) hopefully it helps a little