subwoofer buzz - how to eliminate it


MartinLogan Dynamo 700w 

At low frequencies, it vibrates, like it wants to fall apart. It does have a rubber feet, sitting on a hardwood floor, what could prevent it? Isolation feet? More rubber? Also it's facing the floor but can be turned sideways, would that help?

grislybutter

I use Douk Audio Nobsound isolation feet, which uses springs, under my sub. If your sub isn’t falling apart at the seams, that should help. $30 for a set of 4

You can buy on eBay from the manufacturer here

@grislybutter I initially missed your comment that it's downward firing.  If it were me, I would also use a subwoofer platform with the Nobsound feet on top of it to get the sub raised further above floor level. This combo together will give you cleaner sounding bass and should probably help with the rattling or whatever it is.