Text problems using Tweener

I’m using Tweener to fade movie clips in and out. The movie clips contain both graphics and static text.

My problem is that some text strangely disappears from the movieclip. It appears that boldfaced text is more likely to disappear.

I have broken the text apart (select text block and hit CTRL+b twice to change it to graphics) and this fixes the problem. But obviously that is a very nonelegant solution.

Anyone know of a solution?