Thanks. Actually I had already tried those suggestions, but I did just get it to work.
I opened an old project that was in DV and then captured some more video in that project and it worked.
Then I closed FCP and when I reopened it and started a new project it was fine again. It was as if the timeline was stuck on HDV, no matter how many times I changed the easy setup.
I know there is probably some logical explanation, but it seemed like going back to an old project that already had a DV timeline somehow unstuck it.
Anyway, it now seems to work okay. Thanks for the suggestions.