I have been using a copied version of the 2008 dvd navigation. Its never worked properly, after about 10-30 minutes, it loses conection with the DVD, and just starts searching. eventually says, error reading cd or no cd.
yesterday, i put a original 2001 cd in the nav, and it worked flawlessly.

Now i dont know whether the DVD part of the nav is faulty, which explains why a cd works, or it cant take copied dvds. Copied v31 works.