PDF file disintegration

I maintain seversal PDF documents - created from WORD, within a secure website. Suddenly I am seeing documents breaking down: erratic spacing occurs - for example in my TOC I have the word Reclaimed but ir pdf's as Re claimed. Its ok in WORD.

There is no real pattern.

I am working in Abobe Acrobat 9.2 .

Is there a weird font thing going on? Shoutl I go back to version 7? thnaks, p.