Are you kidding me?
I just bought the exact same model and the radio sounds awesome.
Maybe there is something wrong with yours.
Bring it back to the dealer.
It should have 160Watt 6 CD changer.
Put in a good CD or get a strong radio station and it will blow you away.
You are correct about the driver's seat: much too much lumbar curve, it just punches into my lower back and of course that's with power lumbar flattened out. I've found this across all trims LX to EX-L and all the generation 2008 to 2012. Very sad. Fortunately, the new gen 2013 Accord and later have a vastly improved driver's seat: mild lumbar curve and power adjust if you need it. I think the complaints will go way down for 2013 and later. I'm not surprised at all to see the complaints with 2012 and older. I eval'd the car, but luckily did not buy one.
I'd have to agree with the original poster.
The 160 watt stereo sounds quite muffled.
Maybe the EX-L's 270 watt premium stereo sounds better, but IMO the 160 watt setup sounds worse than the stock stereo in my 2002 Sentra GXE and certainly worse than the Harman Kardon stereo that came with my 2009 Legacy 2.5i SE (same price as an Accord LX-P back then).