I just got new 6X9s and one of them has a slight rattle during a few songs with pretty heavy base :? ...the other one seems fine. I was wondering if that could be a defect in manufacturing, a mistake in installation, or just a quirk we could fix. Any ideas would be great.

Thanks

First off I'de say manufacturer defect (If they are the Sony'* in your sig then no wonder jk) Or it could be that the speaker was damaged by playing heavy bass through speakers that have not been broken in yet. Is the rattling loud? If its not then you could just ignore it...

Don't play loud heavy notes just yet. You need to break them in, before anything. COld weather, also affects it, so does an installer that'* not careful.

if u have the bass too high that can also make it distort, or the treble can do the same thing, also check to make sure nothing is rattling on top of the speaker, sometimes something can get in there and make a noise whenever the speaker is moving a lot