My headphone cable has become flaky, so I've been using a small external
speaker for a while. I now need to change my volume settings so often
that running alsamixer in a terminal each time was beginning to annoy
me. So I looked for a systray-based mixer (I use xmobar with xmonad),
and I found volumeicon
(packaged in Debian as volumeicon-alsa).
I really like volumeicon. The default behaviour is perfectly sensible.
Click the icon to mute, click again to unmute. Hover to see the current
volume level, use the scroll wheel to change it. Middle click to "Open
Mixer", which runs alsamixer in a terminal. Right click to set
"Preferences".
What's more, the preferences are also remarkably sensible. You can pick
the ALSA device and channel to control, and there's a straightforward
menu to change the appearance and behaviour of the icon.
It's been quite a while since I encountered a new program that did
exactly what I wanted with so little fuss.