Congratulations on the new subwoofer. I'm glad you were able to leave it out in the open - one less source of buzzing and rattling to figure out down the road.

You'll be surprised how many things in your room are able to buzz and rattle if you shake the room hard enough smile

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8