RochesterG37

vehicle 2008 g37s coupe 6mt with nav premium bose audio ... i am the type of guy that puts aftermarket systems in all my cars except when i got this car ... i was blown away by the bose 4 subwoofer sound system (2 10's in door and 2 6x9 woofers rear deck) .. i purchased new and never had a problem now 57k miles and 4 years later all of the sudden my bass doesnt sound the same .. the problem i am having is that the speakers are not blown i dont think to me it sounds like the rear woofers are putting out only 25% of the bass that it used too .. i try explaining this to the dealer and they tell me after testing everything that it is performing normally .. they tell me theres nothing they can do .. i feel it is an amplifier issue apparently there are 2 amps .. which ever one is powering rear speakers is not doing its job .. problem is if you havnt heard the system before this problem and then listen to it now .. you would think theres nothing wrong because the front subs are still pounding .. does anyone have any ideas how i can get the dealer to fix this?????? there is definitly a difference in sound .. please help!!!!!!<!-- google_ad_section_end --> the most they can check is that there is power and ground and it has power .. they have no way to tell how much power it is putting out or if the power output is where its supposed to be .. they told me i have to wait till a simliar vehicle comes in so they can compare the sound vs mine .. a 2009 base g37 journey came in and that system sucks compared to mine it MUST be different the subwoofers in the doors of mine sound better than that one does .. i dont understand why my system doesnt sound like it used too and they tell me theres nothing wrong im flippin and i dont understand how to make them fix it because they cant diagnose a problem wtf!<!-- google_ad_section_end --> <!-- / message -->