What remote did you use? I believe that Comcast remotes (both grey or red Ok/Select versions) don't have a 32454 setup code. Do you have an Atlas 1056B03?

I believe these IR signals are NEC1 device 0, subdevice 0. Vol+ is function number 65, while Vol- is 69.

Comcast users with a red OK/Select button could check to see if these signals work by assigning 20752 to the AUX button. Vol- should make the volume go down, and right arrow should make it go up.  If these signals work, then it is possible to permanently assign the EFC 00169 to Vol+ and 00168 to Vol-, using the 994 Command.  (The 1056B03 doesn't accept 994 commands.)

Users with a gray OK/Select button can use AUX 1915, but no buttons are will control the volume.  Instead, assign the above EFCs to the Volume buttons.

Other functions can be found by methodically checking all EFCs fro 00000 to 00255.  Do that by assigning 20752 to the AUX button, and systematically tapping Setup (don't hold it) and entering in an EFC.  The IR signal will be sent when the last of the 5 digit EFC is tapped.