Triggering upside down

[Respectac]

Hi all, new to the forum but a Korg fan for years!
Something happened a while back to my MS-20 mini while it was patched in to my modular, and now I can't get any sound out of it under normal operation/settings. I mean even when all patch cables are plugged out and knobs turned to very basic settings. The only way to get it working correctly is to patch the trigger in to the trigger out, and although this is kind of a solution, I'd rather it was not a permanent one as I'd like to not use up those ports. Has anyone come across anything like this before? Is there possibly a severed connection inside that connects the trigger in/out?
Many thanks,
Paul