Can't lengthen duration of imported PDF's in FCPX?

I need to show a PDF at the bottom of my guitar tutorial for approximately 1 minute. FCPX does not seem to allow me to change the duration of the PDF when imported as a connected clip or in it's own storyline--it only allows me to show the clip for approximately 2 seconds. I have tried changing the duration of the clip in every way that I know how (dragging the edges, changing the settings of still images in preferences, etc.). Even when I apply the "change duration" shortcut (D ^) nothing happens. Any help is much appreciated!
Thanks!

CTRL+D should work. Select the clip, press CTRL+D, enter the new duration on your numeric keypad and confirm. If for some reason this does not work:

Select the clip and press ALT+F to create a freeze frame. You will be able to stretch this out for as long as you wish.

- Ronny

It's the weirdest thing--CTRL+D doesn't seem to work for single page PDF's. However, creating the freeze frame works like a charm! Thanks Ronny!

Can't remember working with a PDF before, but is it layered, by chance?

Within FCPX, layered PSDs act like compound clips. So the media inside the clip needs to be extended before the "clip" can be. Might be the case.