Ok, I have no clue what the post is above mine, buttt, just wanted to let you know that I also ran my machine in auto at first and then switched to straight cpap and seem to be doing better. So, i agree with restedgal that you may want to give that a try and see if your numbers improve. Also, make sure you aren't excessively leaking or that messes everything up too.
Good Luck,
Mist