Sometimes I code with just one earbud in, so I can hear my surroundings.
However, you can often miss out quite a bit of music, perhaps hearing only one guitarist of the two in the band!
Create a file: ~/.asoundrc with the contents:
pcm.mono_right {
type route
slave.pcm "cards.pcm.default"
ttable.0.1 0.5 #in-channel 0, out-channel 1, 50% volume
ttable.1.1 0.5 #in-channel 1, out-channel 1, 50% volume
}
pcm.mono_left {
type route
slave.pcm "cards.pcm.default"
ttable.0.0 0.5 #in-channel 0, out-channel 0, 50% volume
ttable.1.0 0.5 #in-channel 1, out-channel 0, 50% volume
}
# Replacing default device
# choose the correct line and comment another one
#pcm.!default pcm.mono_right
pcm.!default pcm.mono_left
Toggle the comment between the last two lines, or comment them both to disable the script