in my situation the auto setup tried to boost to max(+6) in the lowest portions of the frequency curve while lowering the mid and upper range to almost -12. grantd i don't have a good sub at the moment...waiting on the new HSU VTF3-HO. there would have been a good chance that i would have damaged my sub had i not adjusted it.
Make sure your not trying to boost a null... and even if not a null, 2-3Db boost could be ok but no more than that… I don’t remember the "formula" but for every xDb boost, your sub will have to work x amount of time harder to compensate and it can be very stressful for your sub... Good thing you knew about that stuff and didn't trust the auto setup (your poor sub would have taken a big hit)...