BOSE audio in C43? - Bottom A-pillar speaker -

[noogieman]

on bottom A-pillar below glove box there's a plastic cover in my car near the rubber foot mats.
this is a speaker cover.
i removed this cover and i notice a speaker inside.
is it connected to BOSE amp?
or is it only a speaker for MB telephone which is integrated in the MB Audio30 tapedeck?

CLK w208 had a sub integrated in the centre compartment in backseat, did factory place a sub in A-pillar for w202 with BOSE premium package?

thanks