In this case...
1. Go to Text Messages view, threader veiw that shows the audio icon preview when its not opened.
2. Press and hold on icon
3. Select Save from the list\
4. Now the ringer should be saved in SD/Messages folder
5. Move file to SD Card/ Media/ Audio/ Ringtones/
6. Reboot
7. Set as ringer under Settings / Sound / Phone Ringtone.