Any input on the matter would be greatly appreciated. This is my setup. LOCATION cannot be changed. 60” LCD screen backed into corner of room with PC-Ultra wedged right behind it. We have left literally only approx. a 1-2” gap between the back of the display cabinet and the sub cylinder itself. The plastic back of display is pie/wedge shaped and is acting like a resonance chamber. The wide end of this triangle pie is of course at face of screen with full-length speaker boxes integrated onto display sides running full-length left/right side of screen. The worst audible vibrations are resonating through the display back and rattling in the speaker ends, outer left/right edge of display. Display rests on wood component rack. Metal rollers underneath rack on wood floor (we can not pad the rollers since I pull the whole thing out when added/deleting new components) The cabinet base is 6 component shelves; metal racks for units top two rows, wood base of cabinet is shelf for bottom row. Tamed the component rattles in wood rack and the 50pd center speaker resting on wood shelf above display by using various pads. Affixed strips of dynamat at spaced intervals down back of display plastic cabinet itself, (staying off all air vents) to dampen the cabinets resonance. Not a question of pulling the sub back, as I tend to slightly under integrate sub calb. (after the new wears off) for best blend HT and music and the Ultra is currently running at a fraction of capability. Sub is calb running at ¼ sub gain. –2dB in the Outlaw sub trim, which integrates into room very well (if we can tame last cabinet vibrations. Tuning the sub to 16 or 12Hz tamed the vibrations, but if I bumped up dB’s (to allow for SPL loss due to lower tuning point, vibration levels were back). One test CD that excited the most vibration/buzz in room was Fight Club Track 3. I was happy to note after dynamat application to back of display that most of the rattle and sympathetic vibration (almost a buzzing) through the display out to speaker ends was tamed. The right side speaker still has a rattle, which sounds inaccessibly internal to perhaps a mount-point of speaker itself inside cabinet. The TRADEOFF. Turns out that the back of the display (figures!) must perform a function as a sound board/box for its own speakers which the dynamat is having adverse damping effects upon. Tweaking trim treble/bass in display menu alleviates the issue, but I have lost quite a bit in sound Q. Husband states tradeoff is "good enough" although he freely admits his hearing is not as sensitive or bothered by certain loss or gains in audio quality as my own. I want to start stripping off dynamat from center of back of display to see if I can allow the back to resonate more freely as a sound box, for its own onboard speakers; leaving the outer dynam. strips (towards the speakers) in place to tame the vibration, which exits audibly at left and right edges of cabinet due to subw excitation. Or remove dynamat completely and come up with some sort of barrier between the sub (1 to 2” inches away from the back of display) which interferes with destructive frequency waves exciting the immediate back of the display. He tells me let go and let live. I cannot, - I want both the new sub and the original sound quality out of my extremely above average display speakers. Any alternate ideas?