No baseline shift on that text?
Have you experimented with changing the text around to see if this is truely a localised effect?
We can't see the overall shape to see what is going on.
I'd love to see the original file (click on my blue name and email me) to check whether this actually a bug or merely a consequence of the Design/Layout.
Oh dear, I feel like a right plum now, it was all to do with the baseline afterall, I reset it back to default and all was well in the world again. Such a basic thing to check and I obviously had skirted over that one even though it was blatantly the first thing to look at. Apologies for wasting your time chaps, and thank you for your input as you solved the problem for me. I'll be quiet from now on.