Dead Radio

[malamute]

My 2008 H2 factory radio (no nav) is dead, only the button backlights come on at night.  I have checked and swapped the fuses for the radio and Onstar.  I disconnected the battery and held the positive and negative cables together for a minute (read about it in another post).  My Onstar light comes on, but there is no sound.  I still hear the turn signal sounds, as well as seatbelt warning sound, etc.
 
I have an appointment to bring it to the dealer next week, but was hoping someone on this forum could provide some insight.
 
Thanks for taking the time to consider my issue.
 
 

[gram]

If checking fuses dosnt fix it you will have to pull the radio and check for power at the plug on the back. Gm also likes to put fuses in the back of the radio housing.