Can the sh-w162 rev. c burn lower than 4x?

i just got a sh-w162 revision c from microcenter
when i inserted my verbatim 16x media i can only burn with 4x up to 16x speed. using firmware ts10
when i inserted the same verbatim media on my friends laptop it can burn at lower speeds, 1x and 2x.
can this burner burn at speeds lower than 4x ?
thanks.