Plextor PX-810SA burner speed

Hello my Friends! :slight_smile:

i have two new Plextor PX-810SA and i can’t burn a CD or a DVD at 4x or 8x.

When i choose a speed at Nero or CloneCD to burn the disc the drive doesn’t care and allways burn it at max speed. And it happens in both drives. :a

Would you please be so kind trying to help me? i realy do not know what i must to do to solve the problem. :o

Thank you very much in advance. :bow:

Any idea, please?