When i play it loud in the lower octave. There is a kind of vent noise comming from the left of the rubber. There is nothing loose, everything seem well built. I have read some reviews that were talking about this port or cone shuffling

Nad C356 DAC & C515
Axiom M3v3
Grant Fidelity RPF-120 MKII
Analysis Plus Black Oval 12&10
JRiver 19