Embedded Shockwave File doubles PPT file size

[amosohi]

Hi,

I have a Shockwave Flash file which is 2mb.
I open Powerpoint and embed the flash file using the Shockwave Flash tool into a blank slide. I do nothing else.
I save the powerpoint presentation and the file size of the presentation is about 2mb, which is what I expect, after which I close the presentation.
Now I reopen the presentation with the embedded image, do nothing other than resave the presentation and now the file size is about 4mb.

Any ideas on how the file size has doubled? I have tried this in both Powerpoint 2003 & 2007 yet the same issue occurs.