Run alsamixer
(or alsamixer -c 1
if you get errors) and set mic boost there to some unique value, like 96% (-1,00 db).
You can also change a setting in the gnome menu and try to find it in the listing of pactl list
.
Now run this command but replace the value with yours
export VAL=96%; pactl list | sed -n "/^Source #/{x; /$VAL/p; d; }; /$VAL/H;"