Ring-back tones: A ringback tone (or ringing tone) is an audible indication that is heard on the telephone line by the caller while the phone they are calling is being rung. It is normally a repeated tone, designed to assure the calling party that the called party’s line is ringing, although the ring-back tone may be out of sync with the ringing signal.
If you are choosing to have a ringback tone placed on your line please make sure that it is appropriate! VIP says no to ring back tones in 2015. It is better to play it safe and just remove them if applying for a professional position.