You can purchase an iOpener directly from their website for the same $99.00 price. Also, they use a standard Stereo Yamaha sound processor like used in many onboard sound systems and one could easily trace down the left and right audio signals and add a couple of RCA jacks or an 1/8" stereo jack to the iOpener case.
For $99.00 it is worth it even to use this as a dumb terminal as a front-end for a more powerful, trunk mounted system. The USB port would be an excellent way to link the iOpener to the main PC.
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