GMC 2011 Sierra Denali Owner's Manual page 236

7-48 Infotainment System
To listen to an iPod or portable
audio device through the RSA,
attach the iPod or portable audio
device to the front auxiliary input
(if available), located on the front
audio system. Turn the iPod on,
then choose the front auxiliary input
with the RSA SRCE button.
P
(Power): Press this button to
turn the RSA on or off.
Volume: Turn this knob to increase
or to decrease the volume. The left
knob controls the left headphones
and the right knob controls the right
headphones.
SRCE (Source): Press this
button to switch between the radio
(AM/FM), XM (if equipped),
CD, and if the vehicle has these
features, DVD, front auxiliary, and
rear auxiliary.
(Seek): When listening to FM,
AM, or XM (if equipped), press
either seek arrow to go to the
previous or to the next station or
channels and stay there. This
function is inactive, with some
radios, if the front seat passengers
are listening to the radio.
Press and hold either seek arrow
until the display flashes, to tune to
an individual station. The display
stops flashing after the buttons have
not been pushed for more than
two seconds. This function is
inactive, with some radios, if the
front seat passengers are listening
to the radio.
While listening to a disc, press the
left seek arrow to go back to the
start of the current track or chapter
(if more than ten seconds have
played). Press the right seek arrow
to go to the next track or chapter on
the disc. This function is inactive,
with some radios, if the front seat
passengers are listening to the disc.
When a DVD video menu is being
displayed, press either seek arrow
to perform a cursor up or down on
the menu. Hold either seek arrow to
perform a cursor left or right on
the menu.
PROG (Program): Press this
button to go to the next preset radio
station or channel set on the main
radio. This function is inactive, with
some radios, if the front seat
passengers are listening to the
radio.