If the receiver and sub both have crossover adjustments, should they both be set the same? Should the sub just be set to a certain point and the adjustment done on the receiver or vice versa? I change the receiver slightly between TV and movies and have been just leaving the sub at halfway, but so far I don't really like the way it sounds. My room isn't a very good set up for 6.1. It's a Yamaha receiver and sub.
Depends on how your sub is connected to the receiver. If you are using the LFE pre-out then turn off the subwoofer's crossover (usually by choosing "LFE" not "Normal" mode) since the signal being sent from the receiver's sub pre-out has already been filtered.
The only time you'd use the sub's crossover is if you were using the High-Level Inputs on the sub.