You created a presentation with pictures and music from, the latest school concert and sent it to the other participants . When they try to play it, they see all the pictures, but they don't hear any sound.
At the end of the presentation, you put a movie of the group . It doesn't play, either. But the animated logo you put in does.
The only type of sound files embedded are WAV files. They only embed if they are smaller than the size set in Tools ’ Options.
If the sound files aren't WAV files, you need to send them along with the presentation in order for others to hear them.
Other types of media are never embedded “ they are always linked. If you put movies in a presentation, the original movie files must be sent with the presentation.
So, why did the animated logo work? It was an animated gif. Gifs are considered graphics, not media, so they embed just fine.