You are referring to the lfe level under the sound option and that should stay at 0. The actual sub level is under manual/speaker level along with the rest of your speakers. The lfe section is used like this--I blew my sub and do not have one now so I had to send the lfe to the main speakers so I cut the signal by 10 db to avoid overloading them.
The speaker level is what the ypao will adjust when you run it and will set all speakers to a standard reference level according to your speaker efficiency and the room. Then if you want your sub a little hotter you can bump the level up a couple of dbs.
Hope this helps
James
