You're right, my head skipped over the 16 in your firmware revision number. Can you check if the disk cache is currently enabled? You can do so by runningThere is actually another firmware that was released on 5/30/13 (23.16.0-0012). I've tried both with 23.16.0-0012 & 23.12.0-0013 (which was released on 5/7/13). I can't get the diskcache to be enabled. It's just grayed out in the WebBIOS. I even tried with Cachecade trial key hoping that it'll make a difference but no go...
Are they enabled by default or did you have to choose "enable" from like a drop down menu?
MegaCli -LDGetProp -DskCache -Lall -aALL