I have 2 BV8000pro and with both phones problems with the rear Laustsprecher.
Both phones were purchased through EBAY and the vendors did not report warranty claims.
The first one was bought on 08.08.2017 at the seller @1superbest1 and was broken in April 2018.
The second one was bought on 12.04.2018 at the store @topsuche and is now also defective, loudspeaker rattles and is no longer to understand.
I would like to buy a BV 9500pro or 9600pro, but I am disappointed by the customer service and will probably go to another manufacturer.
I ask for a proposal yur warranty processing !!!!!!!!