Flash object makes MySQL increment by 2

Flash object makes MySQL increment by 2

I have a page with a flash object on it, and I would like to count the
pageviews by incrementing a field by 1 in my database.
The query works fine (tested it in phpMyAdmin) and the function gets
executed only once, but still the field gets incremented by 2 every time I
reload the page.
When I remove the flash object from the page, the field is incremented
only by 1.
Can someone explain why this is the case, and how I can prevent this
behaviour?
Thanks a lot!
PS: This guy seems to have the same problem, but no solution is posted...
mysql wrong column increment