You can lock the door (from the inside) if the key is in the ignition and the door is shut. That is by design. In my 01 the locks do not engage automatically when you put the vehicle in gear so if you want to lock the door while driving you do so by pushing the door lock button down with your...
Since I've owned my 4 Runner (brand new) I have never been able to lock the driver door when it's open - this I believe is a feature meant to prevent you from locking yourself out. The only way to lock the driver door is when it's shut either from the inside or with the key fob or key...
I don't have a JBL system and I get a similar vibration when I open my sun roof all the way. When I stop it 2 inches short of all the way the noise goes away completely. I think we're talking about the same annoying thing but could be wrong.
