Sync issues with PO-20 and PO-28

I have the sync set up as it shows in the manual (and the loads of tutorials on youtube): SY1 to SY4. However, while I can play “live” on the slave unit, I can’t seem to get the patterns to play, and the patterns only play from the master PO. The metronome graphic on the slave unit doesn’t budge, though the play graphic flashes. When I toggle through sync settings, I can hear where the pulse is being transmitted in SY1. Totally baffled as to how to get this functioning! Switching the order of the chain hasn’t helped and the problem is the same. Any help anyone can provide would be greatly appreciated. I got them to sync up ONE TIME, but no luck since and not sure what random ordering of events led it to work the one time.

If you have any means to do so please upload a video somewhere and post a link here. If you followed all the videos and manuals it’s difficult to guess where the problem lies. It might be your POs are faulty though that’d be pretty unusual AFAIK.

Have you tried with a different cable?