I don't think the 2014 provides for local (in the radio) music storage, you need an aux device like a iPod, SD card, etc.
The 2014s do not have a hard drive as previous model radios. It has 16GB of flash memory mostly for its software, Nav and settings storage along with buffering of radio audio. The 8.4A only has 8GB flash.
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
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