when i burn dvd-r/rw with my dvdr16k (dvdr1640p) philips velocity is 0.5x.
in windows there aren't problems.
i have installed debian sid
kernel 22.214.171.124-vanilla (compiled by me);
the problem appears also if i burn dvd with k3b/growisofs.
with dvd+r/rw i don't have problem.
i try with dvd-rw (verbatim 2x) and dvd+rw (verbatim 4x).
in windows to burn a 1,3 GB file i spend 7,30 minutes in linux with nero (k3b) 40 minutes.
i have dma enabled and, i repeat, with dvd+rw i haven't problem.
someone can help me???????????