Control of the device can be done by faking a click on each of the buttons, or submitting a value in the case of the volume control. This can all be done via standard http POST commands.

First, the basic commands. The number after "x=" can vary, I think it's actually the x location on the button image where the mouse was clicked. That doesn't matter since each image only controls one function.

• Play curl --data Play.x=1 http://192.168.1.45/Forms/SoundBridgeNP_1
• Pause curl --data Pause.x=1 http://192.168.1.45/Forms/SoundBridgeNP_1
• Others
• Rinse and repeat for the remaining buttons on the page, if desired:

Prev
Stop
Next
RptOff
Shutoff

• Volume Control
  For volume control, you POST a number between 0 and 100:

curl --data gPageVolume=80 http://192.168.1.45/Forms/SoundBridgeNP_2