I've had an Atomic Pi for a while not but only started to mess with it. One of the features it has is a XMOS dedicated audio codec. Unfortunately it does not enable at boot time on Linux. Make the below a shell script and execute it to bring the magic of audio to life. You might have to run the script using sudo. This needs to be done on every reboot.
echo 349 > /sys/class/gpio/export echo low >/sys/class/gpio/gpio349/direction
echo high > /sys/class/gpio/gpio349/direction
echo 332 > /sys/class/gpio/export echo low >/sys/class/gpio/gpio332/direction
If all goes as it's supposed to then you should have audio through the built on speaker out jacks.