Can only write at 1x useing ritekg05 dvd-

hi
can anyone help
ive got a toshiba sd-r5112 dvd - writer
and been useing ritek4xdvd-r ritekgo4 discs (writing at 4x)
ive just bought another pack, and the disc id is ritekgo5
my writer will only write at 1x with these go5’s
the same thing hapened when i got some datawrite yellows v2’s go4’s
the second pack was go5’s , they also only write at 1x, where as the go4’s will write at 4x no problems
is there anything i can do ?

thanks :confused: