Hey Friends - I have a mono SHIM amp that doesn’t make a good connection unless it’s installed at an angle. I am working with a brand new zero but tested on a PI 3/4 with the same issue. If I shim it (get it!?) at a 20-30 degree angle everything works as show in the image.
I can’t attach images because my account is new, so hopefully a dropbox link works to show what I’m talking about.
I’ve had a similar thing happen with one of my Fan Shims. I plugged a female header in on top of it and it fixed it for me. Might also work for you. Something else you can try is push something non conductive between the two rows of pins on the GPIO. Just spread then apart slightly.
Or, just solder a female header to the bottom side of the shim, and plug it in the normal way.