Volume control

[rsalsbery]

This case is to come up with a method to control the volume from the DAKboard. We need a method to control this from the Settings page and possibly from the screen.

Desired effects:

• Be able to adjust the volume from the CPU for Screens and Speakers that don't have volume controls
• Be able to adjust the volume on the Screen with a slider for touchscreen and mouse interactions

Things to look into for these controls

• Look into alsamixer which is included in the image already
• See about chromium extensions that will work in Kiosk mode

[cocarrig]

a terminal command in the following format will successfully change the volume of the main HDMI-1 on Pi4B in testing:
sudo amixer cset numid=1 70%

Next Steps:
Determine if the % values are to scale, and test on Orange Pi 3 LTS supported device.

[Dan-Peck]

OS IMAGE CHANGES NEEDED

• sudoers will need to add /usr/bin/amixer for www-data sudo privileges

[cocarrig]

Completed and released in version 4.01 for RPi models, will not be supported for OPi models at this time:
https://github.com/dakboard/Hardware-OS/releases/tag/4.01