you need to read the threads on replacing them all with brass screws...Mapleshade and others recommended this, and no, Mapleshade did not sell brass screws and neither did the other companies I saw recommended it...
Got a screw loose?
So based on a comment from another forum, I decided to ensure the screws on all my speaker and subwoofer drivers were secure. Turns out everyone of them needed some level of tightening.
Suggestion: Check your screws, definitely helped tighten up the sound as well.
Question: Is there other “maintenance” I should be doing on a regular basis?