ok I edited the volume control plugin to be more verbose and what I get is:

! volume_constructor cannot open /dev/mixer, errno='No such file or directory'

the printf was added to this piece of code:

    mixer_fd = open ("/dev/mixer", O_RDWR, 0);
    if (mixer_fd < 0) {
        printf("! volume_constructor cannot open /dev/mixer, errno='%s'\n", strerror(errno));

seems like /dev/mixer is not the correct device name...

On Fri, Jul 20, 2012 at 12:45 AM, Giuseppe Penone <giuspen@gmail.com> wrote:

You need to do ./configure --prefix=/usr --with-plugins=all , otherwise you don't have all the plugins enable.

No it doesn't work. Actually I see the plugin "Volume Control" in the list, I can add it but it is not displayed on the panel.
Restarting the panel from the command line then I see "lxpanel: can't start plugin volume".