Originally Posted by
BMWCCA
Obviously this has little to do with a sudden change in sound, but you need more power.
And then, how loud were you playing them?
Under-powering those tweeters at loud volume will distort and blow them. That might account for a flat sound. In which case you should have used more power? Take a cardboard tube (paper towel, wrapping paper) and put it to your ear and the individual drivers to isolate and determine if they are all working. What did you have to "fix" on the speakers before?
Good Luck