Audio Systems: vw gti error 8, auxiliary input adapter, radio tape

Question
on my '98 vw gti, i get an 'error 8' message when i try to use the cassette adapter with my sound system. if i use a new cassette adapter will the error message go away? also, i read in another post that its possible to set up a connection from the back of my head unit with an output in my glovebox or dashboard. what connector/cable would i need for this? many thanks in advance!

Answer
sorry for the delay
the radio tape was made to play tapes only nothing  else that is why you get the error
the best way is to use the auxiliary audio input  
http://www.oemautosound.com/pc-343-176-pie-vwr-aux-volkswagen-98-07-auxiliary-in...

If you have a cd changer use this interface
http://www.oemautosound.com/pc-346-143-pie-x3-vwr-audi-triple-input-auxiliary.as...