I recently purchased a MX-450 and started to setup my devices today. I didn't have any problems with my TV (Panasonic gt30), my Directv, or my XBox. However, my Denon avr1912 has been problematic. After the code screen, when it asks me to test the device, only on and off work. So, I tried to go into learn mode for the volume buttons. The down volume actually worked after learning, but the up volume button isn't working. It says that the function was saved, but the volume won't turn up (it will turn up my TV's volume so the button works). All of the buttons "inside the device" seem to work too. What am I doing wrong?