Help with squeaking driver door
 

Installed the Lanzar OPTI6PM 6.5" mids a month ago and now having a squeaking problem with the driver door, passenger door is fine. Only squeaks when it's almost closed. Took off the door panel and same issue, I can't find or see where it's rubbing, tried WD40 on the 3 joints, I believe it's coming from the black joint but was hoping someone who's installed aftermarket speakers would know? Especially heavy ones like those Lanzar.

Thanks!