Lucky discovery.? To lose 3 units at once... a nightmare.??
You might want to also pull out the Gemini1 board from each unit, and examine the top and bottom for corrosion that could cause shorter battery life....especially the unit that had water in it.
If you do see corrosion or discoloration, you can usually clean it up with alcohol and a cotton swab.
Boy, I was going crazy as all three of my Gem I controllers were going crazy with the same gibberish at start up within a couple of weeks of each other.? One was left outside undercover and had water pouring out of it from condensation (which is a different story).? All were connected to my MI-250.? I swapped EVERYTHING out and set up all controllers inside on my G11.? After hours of fussing around and changing out paddles, cables, internal batteries and checking their voltages, I noticed that the batteries seemed rather loose in their holders.? I typically have to man-handle the clips to get the old batteries out but there have been no problems at all over the years, even with dead batteries.? Then BAM, trouble.??
So, I mashed the clips down before inserting new batteries (again!), bending them as much as I could.? I then inserted the new batteries, noting that the fits were tight to the point that I had difficulty even rotating the batteries in the holders.
And now everything seems to be working just fine.??