I received my replacement amp plate (DSWProWI 550)and got everything hooked up and it seems to be working great! Thank you to everyone here for the help and thank you to Polk for making good on my situation!
I noticed though that the remote I have for my DSWPro 500 doesn't seem to have any affect on the sub now that it's running off of a DSWProWI 550 amp. I had it hooked up, and it didn't work, so I took the unit apart again to see if I had the wires plugged in correctly. Put the amp plate back on a second time and still no luck with the remote. Even tried a new battery in the remote.
Anyone have any ideas? Thanks!