Another possibility is running through my mind here...

You say that this happens with different textures, but presumably you are always using the same bump map.. the one you developed for this character?

The question is: do these artifacts disappear if you set her Face material bump value to zero? (one of pjz99's checks)

If they do disappear, I have a suggestion for you. If they don't, just ignore me.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)