On my laptop, I have an onboard sound card, and also a connected bluetooth headset. I have configured the bluetooth device in /etc/asound.conf:# cat /etc/asound.confpcm.bluetooth {    type bluetooth    device 12:34:56:78:9a:bc    profile auto}ctl.bluetooth {    type bluetooth}Now I can play audio to my headset by specifying the new audio device, such as:mplayer -ao alsa:device=bluetooth file.mp3If I want to play to my default device, I simply omit the device:mplayer file.mp3However, I need to configure ALSA, so that all sound is sent to both devices by default, without having to explicitly set this per application.ie:mplayer file.mp3should play both on the laptop soundcard, as well as in the bluetooth headset.How can I do that ?
ALSA: send audio to two audio devices
audio;alsa;bluetooth