Hi Ichigo,
That's perfectly normal to not necessarily hear a difference between a crossover frequency of 40 Hz and 80 Hz for the M22. And although JohnK and I politely disagree on the virtues and limitations of Audyssey, may I suggest that you not become overly reliant on its calculations. Audyssey and similar systems may be hit or miss and tend to be error-prone.
The default crossover setting for the M22s that tends to work very well in most applications is 80 Hz. Using that allows the subwoofer to gradually take over the deep bass duties so the little woofer/mids in the M22 don't have to "work" as hard and so play more cleanly. Set the M22s to "Small".
Alan
