I have a 2007 with the stock non JBL stereo system. This weekend I noticed when I set the balance to front left there is no sound, not even the dash tweeter. All other speakers work fine. I put my ear down by the door speaker with balance set to the middle and still no sound. Just wondering where I should stark looking. An unplugged wire somewhere, two bad left speakers or is it possible that channel on my stock head unit went out?