FM
FM signals only reach about 16 to 65 km (10 to 40 mi). Although the radio has a built-in electronic circuit that automatically works to reduce interference, some static can occur, especially around tall buildings or hills, causing the sound to fade in and out.
See also:
Unable to Connect to OnStar Message
If there is limited cellular coverage or the cellular network has reached maximum
capacity, this message may come on. Push Q to try the call again or try again after
driving a few miles into anoth ...
Format
The radio can play.mp3 or .wma files that were recorded onto a CD-R or CD-RW disc.
The USB port can play.mp3 and .wma files stored on a USB storage device as well as AAC files that are stored on an i ...
Cellular and GPS Antennas
Avoid placing items over or near the antenna to prevent blocking cellular and GPS signal reception. Cellular reception is required for OnStar to send remote signals to the vehicle. ...