I just bought a brand new alpine cda-7892. I installed it myself in my 93 explorer but no sound comes out of the speakers. Power goes into the HU itself (light flash, able to push buttons and stuff happends), but no sound comes out of the speakers. i put my old deck back in and everything works perfectly, but my no deck does not play a CD or the radio. I connected all the wires right but nothing happends. please help me.