Quote: Originally Posted by
sebberry 
The output on many motherboards is of fairly mediocre quality at best, and if you are offering an HD radio, then being able to take the output and feed it directly into an amp would be the best way to maintain sound quality.
Then again, most people are content with compressed itunes audio quality.
If a user was disappointed with the audio output of their onboard sound I would hope they would get a higher quality sound card or USB audio output device. I assume that most people would want to do more then just play the radio and want the ability to mix several audio sources such as such as mp3s, navigation voices, satellite radio, etc. The advantage of running it through a computer is that it can handle all of that cross fading, mixing, etc and then output a single audio stream. The computer does all of this digitally so there shouldn't be any degradation of the audio signal.
If you wanted to run the audio outputs from each device you have directly into your amp then you would have a amp with a lot of inputs and then manually toggle between inputs.