Hey guys i noticed that in my 2009 is350 that the rear speakers are very quiet and have very little bass. It feels like all of the sound is coming from the front of the car. I have the 'volume position' set to the middle of the car on the audio screen so having it set all the way up the front is not the issue here.

Cheers

 

Your amp is going. It's one of the conditions when it starting to fail.

 

Yep......wet winter weather......and the stupid trunk vents are right behind the tires which is such a perfect spot for rain water to get splashed up into the vent and wet the audio amplifier. In an attempt to prevent more water damage to the amplifier, you can do as my son has done and seal off the trunk vent. He used aluminum tape to seal the vent to try and stop the amplifier from becoming more damaged.......two years later the amplifier began working perfectly again.