To increase the volume, press up the volume switch (
).
To decrease the volume, press down the volume switch (
).

Seek SwitchMazda 6 Owners Manual: Operating Tips for Audio System
WARNING
Always adjust the audio while the vehicle is stopped: Do not adjust
the audio control switches while driving the vehicle. Adjusting the audio while
driving the vehicle is dangerous as it could distract your attention from the vehicle
operation which could lead to a serious accident. E ...
Mazda 6 Owners Manual: Dtc clearing procedure
1. Start the on-board diagnostic test mode.
2. First press the POWER button, then simultaneously press AUDIO CONT button
for 2 seconds or more.
Caution
Before clearing the DTCs, be sure to enter all of them displayed
in the on-board diagnostic test mode in the Audio Repair Order Form. ...