Benq DD DW 1620 pro WOPC Problem

I have this drive with the last firmware B7W9 and i have a problem with the WOPC.When i write dvd with WOPC enable,the result is bad as when i write the same dvd with the WOPC disable.With the old firmware B7T9 I haven’t got problems with the WOPC.ID DVD:PRODISC R04.What i have to do?

Don’t fix something that’s not broken, use the firmware that works for you?