Becker stereo problems

[mbzman]

I'm having some problems with the Becker Grand Prix stereo in my '89 300CE. When I'm not using the radio, I will often use a iPod cassette adapter to play music off an iPod. Today while I was playing music with it the cassette deck started to make funny noises almost as if it was jamming up. I tried to stop the music by ejecting the cassette adapter but it would not come out. Even after trying to turn the radio off the cassette would spool up again as it was still inside the deck thinking I wanted to continue playing the music. I eventually got it out of the deck but now the cassette lights are staying on and I can't get the two rotary motors just behind the cassette door to stop spinning. I disconnected and reconnected the battery and that worked to stop the cassette function of the stereo. It seems to work okay now but I'm afraid to use a cassette out of fear that it may jam up again. Is there anything that I might be able to do to make sure that this does not happen again or will I need to buy a new stereo? Are some cassette adapters better than others?