Keybow Mini - does not turn on, half a volt on 5v rail

My setup is as follows:

  • Keybow Mini
  • Pi Zero v1.2 (not W, hand soldered header)
  • Tried 2 different SD cards
  • Tried multiple USB cables connected to different USB ports. Confirmed they are not just power cables. Tried providing power to the PWR port as well as the USB OTG port.

I’ve not been able to get the keybow to light up the keys or trigger any key presses. On MacOS, I see it show up as a USB device. There is activity from the LED on the Pi - and on pressing a key on the keybow, the light flickers in a particular pattern and then turns off.

I’ve double checked all my solder connections, and I believe they’re good, but I am a novice so aware this could be the issue.

Checking voltages with a meter, I see the Pi is outputting 5v on the header, but on the 5v output on the Keybow, I’m only reading half a volt. Could this indicate an issue with the keybow itself? Any other troubleshooting steps to try?