Your remote is made by UEI, so it uses UEI codes.  For Audio devices, prepend 8 to the 4 digit code.  So the desired code is 80689--but the manual doesn't list this code as built into the remote.

If the remote accepts 994 commands (I doubt that it does) then we can manually add the correct IR commands for each button.  Or, if you have a Comcast or other cable remote that uses UEI codes, we can use the 994 command on those.

test tone    00111
super woofer 1    00227
super woofer 2    00223
super woofer off    00222
dolby surround    00179
theater    00034
hall    00032
stadium    00030
simulated    00028
surround off    00159
vol up    00080
vol down    00076
mute    00083
super woofer +    00097
super woofer -    00093
power    00079
input toggle    00242
bass +    00211
bass -    00207
treble -    00047
treble +    00051
dimmer    00156
delay    00252
balance l    00210
balance r    00206
surround mode    00177