My Ferris sweep works, but only intermittently.

For example, I'll turn it on and it'll work for a bit, then it just stops working. Then if I plug it in through usb, it registers key presses but the wrong key presses, like it'll keep switching between windows and opening random tabs regardless of what key I press. Then if I unplug the keyboard and try typing with my iris, the iris will have the same issue. The only way to fix it is to log out and log back in.

Another issue that's important to note is that one of the keys just doesn't work at all.

Any ideas for troubleshooting/what could be wrong?

Some potential answers: - my home row mods are getting stuck - I'm getting some switch shorting

If either of those are the causes, i don't know how to go about fixing them.

Edit: here's a photo of the soldering. Hopefully it's sufficient. Excuse the excess flux lol https://imgur.com/gallery/3VD6eH0