[SOLVED] Hardware Volume on RPi DigiAMP+ and DAC Pro

[Tim Curtis]

According to the manufacturer its muted by default and GPIO22 controls the mute state, but it doesn't specify whether muted = 1 or 0. https://www.raspberrypi.com/documentatio...audio.html

This command for moode9 series "sudo /var/www/util/sysutil.sh unmute-pi-digiampplus" sets GPIO22 high (1) as can be seen below.

Code:

# Unmute IQaudIO Pi-AMP+, Pi-DigiAMP+
if [[ $1 = "unmute-pi-ampplus" || $1 = "unmute-pi-digiampplus" ]]; then
    CHIP=$(gpiodetect | grep pinctrl | awk 'NR==1 {print}' | cut -d " " -f1)
    gpioset $CHIP 22=1
    exit
fi

If I run the individual command to detect the chip it returns "gpiochip0". This can then be used to set a specific GPIO high (1) or low (0).

Code:

pi@moode9:~ $ CHIP=$(gpiodetect | grep pinctrl | awk 'NR==1 {print}' | cut -d " " -f1)
pi@moode9:~ $ echo $CHIP
gpiochip0

sudo gpioset $CHIP 22=1

You could also try setting the Named I2S device to "IQaudIO Pi-DigiAMP+" and then the unmute code will automatically run during moode startup.

If none of the above works its not obvious to me what might be happening on your end.