I've been having issues with drip feeding my machine.
some weeks it works fine, other weeks it just wont accept the auto button.

I'm leaning towards button failure because last time I got the auto mode to light up, I found I had to push the button in the upper left corner for it to come on. if I pushed the button in the middle nothing happened.

that was a few weeks ago and now it doesn't matter where I push it wont light up. it makes the same click all the other buttons make and "feels" ok.

whats the best way to rule out that the button has a problem?