I've been scanning for a 770 dbus msg for the headphone so that I could trigger a script to mute/unmute whenever headphones are pulled out/plugged in.

I guess before I waste too much time I should ask if anyone has looked into this.

I suggest you open an xterm and type the following to monitor dbus signals:

dbus-monitor --system

then, plug in your headphones, see what happens. You do not need to be root to monitor dbus signals.

[Edit: 05/01/07 11:54 AM ] - looks like there is this message (2007 on 770):

signal sender: 1.12 -> dest=(null destination) interface=org.kernel.kevent; member=change

It looks like it sends the same signal regardless of whether it's being plugged in or being removed.

That is what I was saying no real info from the output as to the cause. I'm really not sure if the signal is from the headphone jack or the screen waking up, or hall swithc etc. There may be a file with the status but I couldn't locate it.