Hummer H2 2009 Owner's Manual page 243

Radios with CD and DVD Audio Output
Only one audio source can be heard through the
speakers at one time. An audio source is defined as
DVD slot, CD slot, XM, FM/AM, Front Auxiliary Jack,
or Rear Auxiliary Jack.
Press the O button to turn the radio on. The radio can
be heard through all of the vehicle speakers.
Front seat passengers can listen to the radio (AM, FM,
or XM) by pressing the BAND button or the DVD/CD AUX
button to select CD slot, DVD slot, front or rear auxiliary
input (if available).
If a playback device is plugged into the radio's front
auxiliary input jack or the rear auxiliary jack, the front seat
passengers are able to listen to playback from this source
through the vehicle speakers. 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 3-118 for more information.
In some vehicles, depending on audio options, the
rear speakers can be muted when the RSA power is
turned on. See Rear Seat Audio (RSA) on page 3-127
for more information.
Playing an MP3 CD-R or CD-RW Disc
The radio with a Six-Disc CD player has the capability
of playing an MP3 CD-R or CD-RW disc. For more
information on how to play an MP3 CD-R or CD-RW disc,
see "Using an MP3" in the index.
Playing an MP3/WMA CD-R or
CD-RW Disc
The radio with a CD and DVD player has the capability
of playing an MP3/WMA CD-R or CD-RW disc. For more
information on how to play an MP3/WMA CD-R or
CD-RW disc, see "Using an MP3" in the index.
CD Messages
CHECK DISC: Radios with a Single CD player or
radios with a Six-Disc player displays CHECK DISC
and/or ejects the CD if an error occurs.
Radios with a CD and DVD player may display other
messages when an error occurs:
Optical Error: The disc was inserted upside down.
Disk Read Error: A disc was inserted with an invalid or
unknown format.
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