If you have any kind of suspension modifications, or simply if you drive your car hard, you will eventually get tired of your CD changer skipping on bumps. Worse even, it does the same with stock suspension. An MP3 player sounds like a good alternative, but the stock head unit does not have a line input, so you end up using an FM modulator or a cassette adapter, which inevitably sacrifices the sound quality. And you probably don't want to do that, especially if you just spent a good deal of money upgrading the audio components in the car.

Here's the solution, a relatively easy way to add a direct line input to your stock head unit without sacrificing any existing functionality. There is a couple of alternative ways, this guide shows how to do it by using the tape deck inputs of the internal amplifier.

Thanks to all SaabCentral forum members who did the research and contributed to the installation guide.