Thanks for your suggestions. I am in the process of sending emails to JVC support. Since the system is still under warranty they are required to fix it, they have a repair shop here in my city that fixes their products. Even thought the problem appears to be with the receiver, I am waiting on the shop to finish the repair they claim they are doing with the sub so I can test it. I doubt that it will work since I tried a different sub on the receiver and the problem was still there.
If I test the sub and it still doesn't work then I will take the receiver in.
The support guy at JVC made a few suggestions and I am waiting on his explanation but in the meantime, do you know what these mean? The guy is suggesting that the problem may be caused by the following;
"there may not be a lot of low frequency information (30hz-150hz)"
"Crossover frequency may be set too hi"
"Front spks might be set to large (speakersettings)"