Sounds like a handy feature. We don't have access to a Sonos, so there's no way James can develop anything for Sonos products.
It may be possible already if you have a Vera controller, since VC works well with Vera and Vera, I think, can control Sonos.
Or, maybe there's some python code online somewhere that you could use with the python plugin. Again, even adapting an existing python script requires having a Sonos to test with, so there's not much we can do from VC headquarters.
I would guess that if one of our more technically inclined users had a Sonos, they would have posted about this already, but you never know. Maybe someone can respond here to your request.