If you were using PulseAudio, couldn't you just force bi-mono on the headphones by doing something like this? https://askubuntu.com/questions/17791/can-i-downm

If you were using PulseAudio, couldn't you just force bi-mono on the headphones by doing something like this? https://askubuntu.com/questions/17791/can-i-downmix-stereo-audio-to-mono https://askubuntu.com/questions/17791/can-i-downmix-stereo-a...