Have Line in for Concert I !!! Finally :-)

Hey, guys! I've got a lot of searching and I'm finally making a reasonable line-in for my Concert I - Radio. It is a quite simple kit to solder yourself, with firmware depending on the radio. The part Simulates being a CD changer. This allows the changer cananl to be selected if you want to connect an external source. If you want to connect an Mp3 player or another volume-reduced device, you better use a preamplifier, so you don't have to turn so loud that you can hear disturbances. This type of preamplifier is available for example. at ebay, they are already disturbed accordingly. The software has programmed an absolute freak, the whole is also for other radios like e.g. all newer concert, Symphony and apparently everything that drives around in the VAG Group available. At least for my Bose radio in the S8 I can confirm that it works. In the radio display is CD1 TR1 or if you press on "CD further" or "Track further" then accordingly CD2 TR2 etc. There is no more audio interruption, as was the case with the CD change before, if you have removed the line line from the original changer plug and instead fed in a line signal.
The kit requires some experience because you only get the parts list.
Since I've been looking for information like this for over a year, I'd like to press it on your eyes.-)

Best regards, Vincent