Download files from here:
https://mega.nz/folder/q5gyiIQJ#52PSXimijag0cETNRaB9wA
Place them in the Interface\AddOns\wa_sounds\ folder
Edit the Weakaura and add the following file path to the custom sound:
Interface\AddOns\wa_sounds\el_sonidito.ogg
You can also use el_sonidito_2.ogg if you want a different portion of the song.
You can get to the file path in the WeakAura by going to Actions Tab > On Show > Play Sound > Sound File Path
Please note: You will need to restart your game to make sure the sounds load in.
May not work properly in LFR, since the debuff refreshes randomly. Will trigger the first time, but will not trigger on refresh.