Are My Speakers blown?

Can blown speakers damage a head unit?

• I have a 1998 4Runner and I have, for the most part, a new sound system. I have a JVC head unit and a Kenwood 12 inch subwoofer. My back door speakers, which are stock, are blown i believe; they do not play at all and Ive kept them in the car. Recently my front door speakers have just been going in and out while playing, and i do not know why. The subwoofer still bumps and plays but the front door speakers do not play. However if i keep the volume low enough, the speakers work and play fine. I tried to take my car to Best Buy, because they installed my head unit. I thought maybe there are loose wires somewhere because of of the sub, however i am no car expert. When i took it to Best Buy, the guy told me that because i have 2 blown speakers in the back, it is damaging my head unit and is ruining it and i will have to buy a new one. Although he did not look at my car at all and told me my problem just by listening to what I said. I have never heard this before so before i buy a whole new expensive head unit, i would like to know if this could be possible and if I remove the blown speakers will it fix my problem? thank you so much!!!

• Answer:

  NO & yea