Problems with new Bindings feature

I’ve downloaded the latest experimental build with the new bind anything to anything feature. This morning I was trying to bind a controller button on my keyboard to the media player. So I went to the Bindings tab of the song, selected New, Learn, pressed the controller button, selected the identified controller as the binding source. I bound it to my song’s media player, and selected play/pause as the action. The Value column indicates “invalid parameter”. Why?

Hey Lee,
There is some on this in this thread near the end RFC: Binding anything to anything

worked fine once I selected the correct type of button!