Spending time banging my head against Ubuntu 11.10 due to a lack of consistency regarding lirc. The upshot of this is that we require a method to control PulseAudio volume from a webserver. Here is one way to do it. It provides mute/unmute and quiet/medium/loud volumes.
Download PulseAudio CGI Volume control
There are a few caveats - the webserver needs to run as the same user as the pulseaudio daemon. apache-mpm-itk is used to do this. It also is a sledgehammer to crack a nut. It is very basic. Other people might use it for nefarious purposes. I highly recommend setting Apache to only serve pages to localhost.