ipod and iphone and the OEM nav system SUCK..
my AV (2010 LTZ) has been in 4 (and going back Tuesday for #5) times for ipod / nav issues.
I have an ipod touch 3rd Gen with O/S 4.2.1 (as recommend by GTAC Engineers).
the ipod has popping and click sounds during playback (sounds like an old LP record)
it hangs and freezes the nav and only a key cycle will after unplugging the ipod will unlock the unit.
it appears to freeze the unit regardless of whether it is the ipod being used for playback or not (had it happen listening to XM radio with ipod plugged in)
if the ipod is plugged in when I start the vehicle it locks up the nav.
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I have tried, Ipod video Gen 5.5, ipod touch gen 2, gen 3 and gen 4 and they all have the same issues.
I have had my usb module, nav unit, onstar and bluetooth unit all replaced based on this ongoing issue.. Now a GM engineer is involved and will be looking at my AV come Tuesday.
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flash drive works without issue..
what I have done is to create several dozen playlists in itunes.. then make folders on the flash drive with the same name as the playlists.. put the songs in the playlist in the order I want them, then drag and drop from itunes to the flash drive.
the flash drive has no search ability like the ipod as it does not have an O/S or Database ability, however the GM unit does read the flash drive in the order in which the songs were copied to the drive, so if you select all in itunes in the order you want them, then drag and drop, they go onto the flash drive in that order..
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but overall ipod and GM integration SUCK, and is at minimum 3 years behind competitors products. (didn't have this issue with my Chrysler, or my wifes Toyota, and when I was test driving Acura and Ford vehicle ipod was plug and play without issue. also GM claims that unless your are running O/S 4.2.1 it is your ipod that is the issue not their product, they only support 4.2.1 nothing before and nothing after.