write error: Input/output error : mixer settings

[flatmax]

When I try to play a test sound, I get "write error: Input/output error".

pi@raspberrypi:~ $ aplay test.wav
Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo
aplay: pcm_write:1939: write error: Input/output error

I did a manual setup of the sound card and/or made some changes to the mixer settings.
My alsamixer for playback looks like so :

alsamixer with no "Output Mixer HiFi" enabled

noOutputMixer.png (29.19 KiB) Viewed 7164 times

[flatmax]

In this case, as "Output Mixer HiFi" is not enabled, ALSA will not playback and has a write error.
To fix, open alsamixer from the command line and use the right/left arrows to highlight the "Output Mixer HiFi" control. Once highlighted press "m" to mute or enable this control. Your mixer will now look like so (press escape to exit) :

alsamixer with "Output Mixer HiFi" enabled

workingOutputMixer.png (28.82 KiB) Viewed 7163 times

You will now be able to play without error :
pi@raspberrypi:~ $ aplay test.wav
Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo
pi@raspberrypi:~ $