Don’t think of -10 as automatic gain, think of it as a gain of 55 (due to the data nature of ADS-B the automatics don’t really work)
With the blue stick an a good antenna start with 44 and see if your range is still ok, you might need to reduce further.
Some more text on gain from me in this thread:
(Thoughts on optimizing gain)
But the advice above is very good, just wanted to leave the link here for some more reading.