In the 1909 thread, Dr_Larry_Pepper identified an issue with MULT EQ which you can read about in his dedicated thread on the issue here
This issue impacts all 2009 models 2309 and below although only impacts the early mfr units prior to roughly Nov 2008. For those of you with a 2309 (not 889), if your serial number is xxxxx15241
or lower (check by either looking at the plate on the back of the AVR or doing the procedure below). If your 2309 serial number is in the affected group, click on the link in my sig and provide me with a non gmail email address and I will provide the update for you to install directly. I also provide additional information on how the install is completed if you follow the links in that post to another post in the 2808 thread.How to find the Serial Number or Main Firmware Version number:
a. Place the 2309 into Standby.
b. Press the small ON/OFF button and turn the 2309 all the way OFF
c. While pressing the DYN VOL and VIDEO SELECT buttons on the front panel, press the smaller power ON/OFF button to place the 2309 in Standby
d. Release the DYN VOL and VIDEO SELECT buttons
e. Press the large On/Standby button and power up the 2309
f. Let the 2309 fully power up
g. Each time the STATUS button is pressed it will cycle through first the serial number, then the Main Firmware version number followed by the sub firmware version numbers.
h. To get out of this mode, simply turn the AVR completely OFF (not in Standby).
NOTE: If you have an 889 and believe this issue impacts your unit
, contact the Denon Help desk directly for authorization to ship it to a Denon Authorized repair center nearest you to have the update installed (as you do not have a RS-232 jack to install the fix yourself).