I also have the JVC RX-744V! I am kind of running into the same problem as you. I have 2 JBL TLX171 floor-standing speakers as my front left and right. I have 1 JBL sattelite center speaker. And I have 1 Polk Audio PSW10 subwoofer. I currently use the subwoofer-out on the receiver to the line-level input on the subwoofer. The problem is, the woofer in the floor-standing speakers are much louder and is dominating the subwoofer. The subwoofer's bass is somewhat small and almost diminished by the JBL's woofers. What I have done is looked through the entire on-screen menu of the receiver and there is absolutely no settings or options for subwoofer. Theres not even a setting to select wether you have small or large front speakers. I found that you can only change the speaker size of the center speaker. Do you think that use speaker-level input/output connection for the subwoofer will fix this problem?