I believe all blu-ray players with multi-channel analog outputs generate an anemic LFE signal - generally down 10db from where it needs to be. Is it possible this is what you are seeing in your testing?
Welcome to AVS. This has been discussed in the official 500 thread. There is no sub test signal in the set-up. Never has been with Panasonic dating back to the BD10. Adjust the DB in the receiver setup menu. Also read the audio set-up thread>