Same problem, did this and thought it fixed it, but it didn’t. If yours is making vibration noise still, I found the problem with mine that may help.
The passive cone that is forward facing (that does not have a magnet) is vulnerable to excessive throw in this design as the magnet and voice coil are not present to arrest the throw. The spider, that light brown corrugated flat disc that connects the cone to the metal basket or frame of the speaker, came unglued on mine. It is hard to spot as you need to push on it to see where the glue has failed, it will lift off the metal frame. At volume it is flapping against the frame of the speaker basket making the vibration. Even though it sounds like a metal vibration this didn’t help it completely resolved it.
So (disconnect it from the power) unscrew and remove the font facing speaker, not the active smaller speaker underneath. I had to unscrew the back panel also to be able to dislodge the speaker by pushing it out from behind.
Unplug connected speaker wires, inspect the spider. Google speaker spider and you’ll see what this is if this is something you are not familiar with.
Look for where the spider has come away from the metal frame
Use super glue to reattach it. It is tricky to get the glue in there between the frame and the spider. Buy a tube with a long narrow spout or be creative. Try and get glue on as much of the dislodged part of the spider and frame. Rubber gloves are useful that stuff is sticky :)
your done! Give it 20 minutes to stick, put it back together and you’re done. The more patient you are the better before cranking it up I’d suggest. Mine is completely vibration free at ‘full’ volume now. You’ll know immediately when you put it back on.