Hello, I have such a problem. I have 04 S40 with Performance audio system (6 speakers and 2x40 amplifier). So I decided to install original High Performance audio system with 8 better speakers and a 4x40 amplifier. I installed everything and music doesn't play. What should I do? Maybe the amplifier must be somehow connected with the computer? Or some kind of High Performance software must be installed? Thank you for your answers.