Tools and supplies: T20 Torx Driver, Electrical Tape, (2) Cable Ties
1. Remove cargo cover and cargo floor.
2. Remove screw by the cargo light:
3. Remove center-rear cover, the one that has the opening for the hatch latch. Just pull straight up. There are four metal clips (red arrows) that go into four slots (yellow arrows). Driver's side shown but passenger side is the same. This is one of those "just pull" items. You might be able to get your hands up underneath and squeeze the metal clips but I got it by just pulling.
4. Get the rear lip of the drivers side cargo area panel loose by pulling it out from under the rear hatch seal.
5. Pull the rear of the panel away from the side and press down on the plastic part that is level with the cargo cover. There are two tabs that should be pressed downward to get them to release (red arrows). DON'T pull too hard. You'll need to disconnect the cargo light and it's on a pretty short leash (yellow arrow).
6. There is another "just pull" metal clip towards the front (red arrow).
7. That's as far as you need to go with removing the panel. You can now remove the four screws that hold the speaker and cover. Remove two speaker terminals, one from each side that are the same type. I.E. both narrow terminals or both wide terminals. Here's a pic showing the terminals removed:
8. Tape the loose terminals out of the way with electrical tape and put a cable tie around it to prevent the electrical tape from coming loose.
AIROR (Assembly Is Reverse Of Removal)
When installing the center-rear cover, be sure to get the two slotted tabs on the cover to go behind the two posts before snapping into place.
Results: Much better sound. I had a CD playing during the entire process (Styx - The Grand Illusion) and as soon as the speaker came loose of its plastic enclosure, the heavy thumping and fluttering went away. The plastic speaker enclosure appears to be the cause of the problem. I've now got bass at +3 and treble at +2 and it sounds darn good to me. Plenty of good bass sound without the annoying thumping and fluttering. I cranked up "Castle Walls" and