PosterGrid poster selection plays wrong sound effect

I’ve used PosterGrids before, so I know what sound effect is supposed to be played when you select a poster, but my current channel under development is playing the dead end “thunk” sound when pressing OK on a highlighted poster. I can’t for the life of me figure out what’s different in my new channel from my old channels. I thought I’d try a simple example like Roku’s own PosterGrid example and sure enough it does the same thing when selecting a poster - thunk! I thought maybe it was because there was no handler for itemSelected, but adding one doesn’t seem to make a difference.

If anyone has any ideas or can tell me why Roku’s own example goes “thunk” I’d love to hear it. It’s things like this that make be hate scene graph. I could spend a week trying to figure this out or just say bleep it and I’m not doing the former.

-JT