GMC 2010 Sierra Owner's Manual page 324

RPT (Repeat): For the AM-FM Radio with CD, press
and release the RPT button to repeat the current track.
An arrow symbol displays. Press RPT again to turn off
repeat play.
BAND: Press to listen to the radio when a CD is
playing. The CD remains inside the radio for future
listening.
For the radio with CD and DVD, press to listen to the
radio when a CD or DVD is playing. The CD or DVD
remains inside the radio for future listening or for
viewing entertainment.
CD/AUX (CD/Auxiliary): Press to play a CD when
listening to the radio. The CD icon and a message
showing the disc and/or track number displays when a
CD is in the player. Press again and the system
automatically searches for an auxiliary input device,
such as a portable audio player. If a portable audio
player is not connected, No Input Device Found
displays.
4-100
DVD/CD AUX (Auxiliary): Press this button to cycle
through DVD, CD, or Auxiliary when listening to the
radio. The DVD/CD text tab and a message showing
the track or chapter number displays when a disc is in
either slot. Press this button again and the system
automatically searches for an auxiliary input device,
such as a portable audio player. If a portable audio
player is not connected, No Aux Input Device displays.
If a disc is in both the DVD slot and the CD slot the
DVD/CD AUX button cycles between the two sources
and does not indicate No Aux Input Device . If a front
auxiliary device is connected, the DVD/CD AUX button
cycles through all available options, such as: DVD slot,
CD slot, Front Auxiliary, and Rear Auxiliary (if available).
See Using the Auxiliary Input Jack(s) later in this
section, or Audio/Video (A/V) Jacks under, Rear Seat
Entertainment (RSE) System on page 4 136 for more
information.
If a disc is inserted into top DVD slot, the rear seat
operator can turn on the video screen and use the
remote control to navigate the CD (tracks only) through
the remote control.