I didn’t spend any more time with it. In VSig, the GenderBender preset is mainly made from the SourceAnalyzer/Ultrashifter modules which seem kind of black box and aren’t documented much. I didn’t try to experiment with it. The seller I bought my H8000FW from had it serviced at Eventide just before, so it’s less likely I have a hardware problem.
At least I’m not the only one who noticed it. I guess everyone else only cares about the reverbs and no one is trying to use it to sing the high female backing vocals in their songs.:)