Impress wont add my audiofile

Dear people of this forum, i need your help.

I use LibreOffice Impress. When i add an audiofile to my presentation everything works fine and it plays the file.
But when i send the presentation to a friend, the audiofile is not in the presentation.
Now i checked if the impress file gets bigger after i added the audio, and it does not.
It seems like the audio is only linked to my file on the pc but i want it in the presentation.

Can you help me?
Thank you very much.

When you insert audio or video files using the Insert menu → audio or video… ensure the link checkbox is unticked. This embeds the audio/video into the document rather than calling it from the filesystem.

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