I wrote:
So I feel very sad. I thought I had broken my keyboard jinx. But it’s currently zero for three.
Ummm ... make that one for three. I took the keyboard off the dead pile, and tried messing about with it a bit more. I noticed that every time I plugged it into a USB port, the indicator lights flashed briefly. Can’t remember if it did that before. But still, none of the keys worked. So I assumed it was some kind of error indication or something. Then, with nothing else left to lose, I gave it a moderate whack on the top of my desk. And the volume knob came to life! I tried pressing a few keys; and they worked, too! Some didn’t. But I found that, if I pressed hard and repeatedly on the malfunctioning ones, I could get them working. So, as of now, everything is functioning again. So I doubt there was any actual electrical damage from water, since I assume that would have been permanent. Dirt lodged somewhere? Anyway, I am pleased to have my Das Keyboard 4 back again from the dead. I hope it stays that way ...