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: Ignition switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the ignition switch connectors.
4. Inspect for continuity between the ignition switch terminals using an
ohmmeter.
If not as specified, replace the ignition switch.
...
Mazda 6 Owners Manual: Rear Window Defogger
The rear window defogger clears fog from the rear window.
The ignition must be switched ON to use the defogger.
Press the switch to turn on the rear window defogger. The rear window defogger
operates for about 15 minutes and then turns off automatically.
The indicator light illuminates when the ...