Powerpoint created by PC does not play video on Mac

[bigger2034]

Version: 2004
Operating System: Mac OS X 10.5 (Leopard)
Processor: Power PC

Hope someone can help!
An associate wants to play his Powerpoint presentation on our Mac (10.5.8 with Powerpoint 2004 up-to-date).
Powerpoint presentation includes sound, stills and video. Sounds plays, but the videos do not. Videos will play independently in Quicktime and also if double-clicked within the opened PP file, but not in slide show/full screen. Video files are Mpeg1. Have tried on two different Macs with same result.
Have searched forums without success. Any ideas?

 

[Doug001]

I have this problem... strange thing is that the PPT file was working properly until last night, when a few extra slides were added. After that, the video wouldn't display. I am investigating, and will post back if I find anything.