Photoshop: Won't save all slices in same format

While I'm here, I've got to mention this: This thing where, every time I do my Save for Web, it tells me that my image is much larger than Save for Web was meant to deal with -- this is REALLY annoying when I have to save 50 slices one at a time. I KNOW the image is bigger than that; do you have to tell me EVERY TIME?? Why isn't there a way to shut that off?

Are you selecting all the Slices and setting the optimization settings to the same? Sounds like your user slices are set to a different format than the auto-slices in the document.

That's what I thought, too, so I tried it a few times, making very sure that everything was selected and all of the settings were what I wanted. I get the wrong thing for all but the first and last slice, so now I'm stuck saving a zillion slices manually.

This used to work, so I don't know why it changed.