After playing my sub at high levels over the weekend, it came to my attention that -- what I once thought was driver distortion / buzzing when pushing the LFM-1 hard -- was actually vibration from the top of the cabinet. I think it may be the plexiglass top. Anyway, when I pushed down on the top of the sub during playback, the noise stopped. I tried to think of some sort way to dampen the cabinet. I had three unused VPI magic bricks laying around, so I tried various placement of these along the top. After a few minutes experimentation, I found the trouble zone was the back end of the cabinet (toward the amp). I placed the VPI bricks three in a row at that location and now the buzzing / distortion is gone.

Now I'm a happy camper, but I am wondering if anyone else experience this issue???
Outlaw 970
McCormack DNA-125 (mains), Emotiva LPA-1 (surrounds)
Quad 11L (F&C) Wharfedale (R) LFM1 (Sub) w/ SMS-1
Squeezebox -> Behringer SRC2496 -> Musiland MD10 DAC
Sota Sapphire; Marantz 10B;
Video: Hitachi 42HDS52A; Oppo 971H
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