Don't use "floating", and use "play in page" instead. You have to see the playbar on the first page, but at least you don't see it on every page.
Unfortunately, the new Acrobat is not very friendly to those of us who use sound in our PDFs. For some strange reason Adobe crippled audio features in Acrobat and decided that PDFs MUST have a visible playback bar even when they make our creations look terrible. (sigh)
You can check our Steve's article on a work around if you use InDesign.
Hiding Sound Files in an Interactive PDF
Your best bet may be reverting to an older version of Acrobat that actually worked, like CS3.
