knocking sound on one side of the woofer domes

[ragwo]

If you shake the speaker, do you hear a rattling sound? I've opened several Phantoms and you would be super unlucky to have a loose nut. Devialet uses generous amounts of locktite to secure the nut. If the nut is loose, you should be able to split the speaker in half if you remove the nut under the blue warranty void/do not open sticker hidden under the side panel of the speaker. If you have to remove the metal dust cap the easiest way is to use a scalpel to cut it loose. Please see instructions and pictures on how to open the speaker and remove the dust cap.
https://devialetchat.com/Thread-My-Phant...age?page=5