version 4.2.6.3, EN, Impress, Ubuntu 14.04, EN, How to insert music into existing slide show

I need to add music to an existing document. Document was originally created using Power Point.

Inserting Music and video seems to be ‘borked’ in the current version 4.* that I have installed on my main machine. Works ok in Version 3 which I have still on an old laptop…
If you can try using an old Version 3 of LO then that may answer your question as to whether it is possible or not