Here is my problem that I also posted in the Macbook forum, asking can the internal combo drive read DVD+R DL discs:
So I have an external Lacie DVD burner, which supports DL at write speeds of 4X, if my memory serves. So I plug it into my new Macbook, put in a Memorex 2.4x DL disc, and use Finder to burn a folder. It seems to work fine, and the Leopard verifies it, everything fine there too.
So I take the newly burnt disc out and insert it into the internal Combo drive, and nothing. Just hums for about 20 seconds, then ejects it.
Any ideas? I thought perhaps it was the write speed, and I tried to set it at 1x, but couldn't go any lower than 2.4x when I selected the drop down menu. I tried to set it at 1x because I couldn't remember the write speed for DL discs; I bought this burner about two years ago. Why would it verify the disc if it didn't burn correctly?
I haven't yet checked to see if the external drive will read it; I didn't try the disc in the internal slot until today because I assumed it would work; I'm not at home right now so I can't check.