Greetings from a new owner of a 2012 base CTS4. I have done searches on the forum, but haven't found the answer. Our CTS has a Bose system with single CD changer. The owners manual says:

Digital Signal
Processing (DSP)
If the radio has this feature, it has
either a Bose® sound system or a
Bose® 5.1 Cabin Surround® sound
system. DSP is used to provide a
choice of different listening
To choose a DSP setting:
1. Press the TUNE/TONE knob to
display the tone/speaker and
DSP tabs.
2. Press the softkey under the
DSP tab.

I have tried to find the DSP menu by pressing the TUNE/TONE knob, but only find the menu for the tone settings. I have tried this with my MP3 player plugged into the Aux input and selecting AUX as the input, but still don't see the DSP settings menu to try the different settings, such as Centerpoint. Am I doing something wrong, or am I reading the part in the manual that says "If the radio has this feature, it has either a Bose sound system....etc". In other words, do all Bose systems in a 2012 CTS have DSP?