Recently purchased 08 fx35 with bose system, and even tho all speakers are working , all the sound appears to be coming from speaker atop middle dash. No instrument detail or surround sound . My other car also has bose system and you can pick out different string instruments on different speakers etc. So, what is the procedure for 'tuning' the speakers? I have looked in the manual and balanced speakers but to no avail. Thanks for any and all help. .