Left ctrl key seems to have called quits. No longer reliably works when pressed. Thanks to the on board testing tool I can see what is happening. The key releases after the tactile bump even while its still being held down. Also the inboard diagnostic also detects chatter as soon as pressing the key. Any advice on what to try, next. The keyboard is pretty much stock no plugins added, just swapped default space and delete key locations.
Fixed it by cleaning just the left control key in the prescribed keyboardio way again.