Strange sound from speakers

I just purchased a used 2009 tacoma double cab with the jbl system. I keep hearing a grumbling or crackling sound after the bass when i play the radio or a CD. Has anyone experienced this before?

Thanks for any help you can provide.

 

have you tried turning the bass down to see if it goes away?

 

With bass at 0 I do not hear anything. When i move it up to 2 or 3 I hear the rumbling. Does not seem it like it should happen at such low volumes. I am not sure if it is a system problem or something in the back of the truck vibrating.

 

the only thing i can think of is that the speaker or speakers may be worn out and not totally blown but could be tearing or getting ready to blow. that's the only thing i can think of that would possibly do that other than that idk man sorry. hopefully someone can give a better insight to it. GL.

 

yeah that sounds like your speakers are about to blow...

 

Thanks,
I should have really tested them before picking the car up. I should go back to the dealer and tell him about it. Thanks for all of your help.

 

Typically what has happened is what is called the "surround" fails. The surround is the rubber/cloth/synthetic material "surrounding" the speaker cone and connecting it to the speaker frame. When it fails the cone is trying to drive in and out but not in a straight line since there's nothing holding it in the proper position.