I've have nero for a long time and never had this problem until i recently bought nero ultra like 5 months ago. It was working fine with burning up to 48x and then one day it just start burning at 4x even when check maximum speed, and i assure you it's not the cds since it is capable of burning at 48x and the dvd burner, or cd burner is capable of 48x too. The dvd burner/cd burner are new so it's not dying or anything of that. I try to see if the dma is set up right and yes it is, so i figure out it has to be nero, even if i reinstall it; it still give me the same problem. Atleast it works, but burning at 4x get on my nerve since i didn't spend money to just burn at 4x....Any solution would help out thanks.
Sorry I took so long to reply back, but yes i check everything from disc speed to disc drive and all set to 48x, even when i get to your screen shot i get 48x, but when burn it goes to 4x....
