DVD player says "wrong disc type" (by 3 users)

This seems to be an issue with playing NEWER DVDs. Mine will play some quite reliably, but some newer ones (an no they are not scratched, they are not dupes, they are not imports) get the "Wrong Disc Type" message.

I assume this is a collision due to some anti-duplication trickiness on the DVD producer, somehow encoding the disc with a zero length track or other similar B.S. combined with RCA's lameness at overcoming it.

i have this JNC portable dvd. it has no problem before, but one time, when i inserted a disc, it says "wrong disc". until now, whenever I'm putting DVDs in it, it still says''wrong disc".. I need help! please! Help me with this..