I’m having the same issue with one switch as well. My guess is it’s related to one of the SOC BGA pins not making contact. Have you tried reflowing the SOC?
This might be similar to your issue. I’ve just confirmed in my case the issue is an soc connection. Specifically the outter most line on the left coming out of the bottom of PI3 chip. It was open and I didn’t notice. It goes around the soc to the top right corner on side A. I was able to apply pressure by squeezing the soc with my fingers and it closed the connection.