Transition sounds play across slides by default but AFAIK they cannot be made to loop. The only possibility is to use a free sound editor like Audacity and add some sound to make the original longer.

To recover the sound if you don't have the original try saving Type = Html Web Page. You should get a folder with all dependant files (including the wav file)



You could then insert it "normally" and set it to stop after 999 slides and repeat.

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JohnWilson,
Thanks for the info.
I saved in HTML and obtained the sound file.

I inserted the sound file set it to stop after 999 slides.
For the transition on the first slide I had to select "No Sound" as the embedded sound and the one I inserted clashed.

When playing the slideshow, the music stopped about 4 slides from the end, to fix this I selected the sound icon and selected "Edit sound object" and placed a tick in "Loop until Stopped".

Now all is working OK.

One last question, is there any way to remove the original embedded sound?

kevsim