System Description: Muting
The audio unit orchestrates all muting logic. All voice commands are broadcast over the front audio speakers. Because the OnStar system provides emergency assistance, it has the highest priority for audio output. The priority of the other audio inputs are as follows: HFL, XM-AcuraLink messages, navigation voice, and audio unit CD/DVD or AM-FM-XM music channels.
NOTE:
The USA: Base model retains all the navigation hardware; however the database and DVD have been removed. The USA: Base model also has no navigation features, but retains navigation system components to operate the voice control features for audio system and HVAC. The USA: Base model is equipped with a CD-ROM that displays a compass on the display panel.
Refer to the appropriate following article
for specific tests and troubleshooting procedures.