Another member (thanks, slideways03) had the same problem as me and contacted Klipsch. Important information others might find useful is as follows:
[quoted from an email from slideways03]
"They had no doubt that it was the onboard amp that went bad. I now have to ship the plate to them so they can replace the amp. They charge a flat rate of $75 for the repairs and shipping back to you. You have to pay shipping fees to send it to them. Just wanted to pass that info along to you. The customer Service number is 1-888-554-5665"
I had already taken pictures and wanted to post them. I only see one capacitor(?) that looks obviously corroded and some glue(?) that is melted all over the place. I took an excessive number of pictures...but I thought too many was better than too few. Most of us aren't paying for bandwith yet, anyway...[just kidding...i downsized them first]
[plate amp from various angles]
I will probably end up sending this off...but will likely hold on to it for a few weeks in case someone else cares to share some knowledge with myself and any others who could be helped. The strangest thing to me is that the bass seems fine...I thought it was muddy sounding, but I think I'm just not used to hearing nothing but the sub...was working on it today to take the pictures and it just sounded like neighbors a couple of houses down were having a party...
Thanks everyone for looking!