How I made the links above
1) I typed the following: Audio link 1
2) I highlighted the whole phrase: ‘Audio link 1’
3) I pressed the link button above the text box
4) I typed the link address in the first box (starting with https, and ending with mp3)
5) I left the second box empty, and pressed the ‘add link’ button
It seems this is the only way of getting audio links to work here!