One problem that can occur on Volkswagon CD players is when discs get stuck inside of the system, and the player becomes useless. This can be corrected in a number of ways that can be tried without harming the system.
Turn your car ignition to the "Acc" position with your key. Press and hold the "Eject" button on the player for as many as three minutes to try to force out the disc.
Press the "Power" button on and off while holding "Eject" to try to get the system to power up the ejecting process while turning on and off.
Reset the system with the reset button on the front of the player. Hold the button until the player powers down, reconfigures itself and turns back on. This might force the disc out as the player powers back on or off.
Insert the tip of another disc or small object into the player and attempt to lodge it beneath the stuck CD to push it upward into the ejecting track, which will then push the disc out once the eject sequence activates.