aftermarket stereo

I recently decided to upgrade the stereo in my 2006 smart forfour so i can use bluetooth i have tried 2 stereos and neither are powering up you can here the power supply when connected from mechanical movements in the cd wht is the problem?

Correct wiring an aftermarket stereo head unit for your 2001 Chevrolet Suburban, will ensure maximum functionality and increased reliability of the car audio system. Apart from using a vehicle-specific installation kit to properly install aftermarket radio, making the necessary wiring...