Sorry to jump in so late, but I'm afraid I'm another victim of Marantz LFE coarse. I live in Brazil (where electronics are very expensive) and I wanted to upgrade my HT system (Yamaha RXV-520 rcvr) so, as I was going to spend a few days in NJ in August, I bidded for the 8400 on Ubid in May and unfortunately I "won".
Upon arriving in NJ, I just tested the receiver with 2 channel. As it turned on and was "speaking", I thought it was OK, so I packed it back and brought it home (Rio de Janeiro).
How dispappointed I was to see that it could not drive my sub properly. It looks like the bass is fainting, farting or clipping (sorry I'm not native English speaker), weak and boomy. Even cranking the sub volume up, the LFE is weird. I kept trying settings of volume, surround modes etc, exchanging subs and cables to check if it was the sub, but now I found that other people in this forum have had the same problem. Besides, both my subs sound great with my old Yamaha.
I'd like to know what other victims like buchinmj and jdcohen (who reported this problem in this forum) got from Marantz. Is it worth complaining? My situation is critical because I'm out of the US and warranty might not apply here. So, I don't believe Marantz will honor their reputation, even though they have one representative in Brazil, cause it was not bought from them.
I guess it might be a problem of processing the LFE signal. What would the repair be, if any? Just replace one faulty module? Or would it be a project defect? Might it be a QC rejected lot that they sent out through Ubid?
Any help will be appreciated.