Problem reading dvds with nec 3540?

I purchased an nec 3540 from newegg. I bought some dvd’s off and they were all copies. Before I returned them I stuck them in my computers.

My computer with the pioneer 108 was able to read all 4 of them. They all read as 4.35gb. 2 of the movies were over 2h and 20min so there is no way they were single layer dvds…

but my computer with the nec 3540 could only read 1 of the 4. The nec appears to read regular dvd movies and dvd games fine.

Do you think I might have a problem with my nec? I was wondering if I should return it before it runs out of warranty. Is there a real good way to test my drive? I was able to burn a dvd and it worked fine.

thanks in advance for any help/advice. Later, Bill