I e-mailed Definitive Technology and a customer service technician responded quickly saying plug the sub up and listen for a 'thump' and unplug it and listen for a 'thump'. He, Thomas, also told me to run my finger across the end of the subwoofer cable while the other end is connected to sub, I suppose the LFE port, and listen for humming and/or popping. I told him I heard no 'thump' while plugging and unplugging the sub, and running my finger across the other end of the subwoofer cable, heard no humming and/or popping noise.
I tried another rca cable and it didn't work. It was probably an unshielded cable though, one used for stereo audio (I used the White one and not the red one).
My receiver has my speaker settings set as Front - Small, Center - Small, and Surround - Small, Subwoofer - Yes, and two other speaker settings, but it was set to No I think (I think it was the height speakers or something, it's a 5.1 receiver). I do like to comment on one thing though. The receiver, Pioneer VSX-522, set my front to Large and the others to small when I ran the auto config with the microphone. I thought that was strange because my front speakers are wired straight to the receiver, not to a sub via speaker high level inputs (spring-clip sockets).
I will see tomorrow, hopefully, what he says the problem is. Maybe a defective sub, even though I got it brand new...shucks.