Sonos controls on a Mac?

I would like to control the Sonos client with keyboard shortcuts. I can reliably pause/unpause with Consumer_PlaySlashPause. What’s the magic for changing volume? I tried both Consumer_VolumeIncrement and Consumer_AlternateAudioIncrement (and of course the corresponding decrements) and neither one of those worked. And while I’m here, what are the track forward/backward buttons?

thanks!