This unit plays audio files as follows:

CAUTION
Do not use an audio file extension on files other than audio files. In addition, do not change the audio file extension. Otherwise, the unit will not recognize the file correctly resulting in noise or a malfunction.
NOTE
MP3/WMA/AAC/OGG files written under specifications other than the indicated specification may not play normally or files/folder names may not display correctly.
Operating Tips for OGG
Audio SetMazda 6 Owners Manual: Electrical parts
Battery cable
Before disconnecting connectors or removing electrical parts, disconnect
the negative battery cable.
Wiring Harness
To remove the wiring harness from the clip in the
engine room, pry up the hook of the clip using a
flathead screwdriver.
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Mazda 6 Owners Manual: Operating Tips for AAC
AAC stands for Advanced Audio Coding, which is standardized voice compression
established by the ISO*1 working group (MPEG). Audio data can be created and stored
at a higher compression ratio than MP3.
This unit plays files with the extensions (.aac/.m4a/.wav) as the AAC files.
*1 Internationa ...