My speaker in the back of my car keeps making a crackling noise? They are factory speakers hooked up to a Sony Radio 55WX4. The speakers are in the trunk with my subs. Is this being caused by interference with something, or are the speaker blown? I am going to replace them eventually with sony 2 way speakers in the front and 3 way speakers in the back, will this sound good?

Since they are factory speakers, and you're powering them with an aftermarket deck, you more than likely blew them. Aftermarket radios are going to produce more power than a factory deck can. You more than likely pushed more power to the factory speakers than they could handle. The Sony speakers will sound better than the factory speakers.

ya l think its blown

put your 3 way speakers in the front