middle box rattling again??

[marksman]

couple of weeks ago had a new standard cat back exhaust fitted ,then the centre section started to rattle when warm ,so took it back and they replaced with a new one ,3 weeks later and this one has started to rattle now!!!!!
dont know weather to take it back a 3rd time or get a straight through pipe ?
can anyone recomend place , price , make ,if this is the best way to go ,,,,cheers for any help

 

[Brasseye]

if its free get another box...
else youll pay extra on the insurance