Hello!

It there a way to turn off or down both rear speakers, leaving just the front ones working ? I don't see anything the owners manual

 

It's called "fade". IIRC, it is in the "menu".

I just checked my 2011 Owners Manual; I wonder why they don't mention the radio.

from the 2008 manual page 3-66
Adjusting the Speakers (Balance/Fade)
(Radio with CD (Base))
`
BAL/FADE (Balance/Fade): To adjust the balance
or fade, press this button or the
f
knob until the desired
speaker control label displays. Turn the
f
knob
clockwise or counterclockwise to adjust the setting.

(f is as close as this editor gets to the music bar thingie, the knob on the right)

 

Welcome to the site.

Look on page 4-68 of the 2010 owners manual.(the OP's listed year model)
There is a whole page about adjusting the speakers.

To clarify: Balance is for left to right speaker adjustment.
Fade is for the front to back adjustment.

 

Oh, there it is! In the 2011 it's 4-59. Under Audio System(s).

 

Thank you folks, will give it a shot.