superpenut's dashboard

I have an auto-advance duration set to 2 seconds in Master Properties. There are 3 slides that I want to auto-advance in 3 seconds rather than 2. The Override Slide Properties check box is clear.

If I change the auto-advance in the slides "slide info" configuration to 3 seconds, then save the document and preview it works fine. If I exit out and go back in, it always reverts to one second, rather than 3 on the 3 slides in question. I think this is a bug. Please let me know if I am doing something wrong. Thank you.