https://forum.audacityteam.org/t/karaoke-rotation-panning-more/30112/1
has an isolation function built-in.
However, the background noise and especially the speech is very broad spread.
Thus, the ringing can almost perfectly be removed, but the opposite is not the case.
That’s about the best you can expect:
It is made with the above tool, “Isolate vocals” and a rotation setting of 22 degrees (effect parameter).
The rotation shifts the ring tone towards the right speaker (the speech). The isolated band is therefore between ring tone and other noise (paper shuffling?).
The sample is a little short, isn’t it.
If you have a ringtone that repeats its pattern a few times, the result can be improved as follows:
- Isolate the center (only with the above tool possible)
- make the stereo file mono (track menu)
- split the track into two parts (or more) where a repetition begins.
- align two tracks and make them stereo.
- repeat the steps.
However, if the ring tone isn’t more exciting than in the beginning, it would be easier to generate it from scratch or to search on freesound.org and similar.