Oppo 105. Problems with crossover?

Recently added sub to current 2 channel set up. Using sub out and Oppo crossover. I have tried many different crossover points with little to NO audible difference. Is Anyone else experiencing the same issue?
As it stands, my Merlin VSMs seem to be running full range. 
Have you read the Oppo "Knowledge Base" article on this subject:


May help?
Thanks. I will try the different settings mentioned and see what happens. Sounds as if full range or crossover is an option for mains. 

Are the main speakers set to "Large"? They must be set to "Small" for the Bass Management to work.

changed stereo signal from stereo to front right/left and crossover works now. Seems like that info would have been in the manual. 
Thanks again