There are several attributes inherent in the soul which appears and re-appears in all the births. This is witnessed in Shankukarna carrying his love for music in all his subsequent births. It is evident here-  

Shankukarna gets engrossed in Devine Veena music of Goddess Sharadha makes it a cause for several births to serve the mankind. Later born as bhaktha Prahalad gets the privilege of listening to thambura music played by sage Narada praising Lord Narayana  while he was still in the womb of his mother. Further born as Vyasa Teertha, his composition of Krishna ne Beagane Baaro, his soulfull song making Lord Krishna and consorts dance at Mulabhagal Mutt, Vyasyaraja, the Musicologist initiation to Purandaradasa and Kanakadas. The latest birth as venkatanatha  Goddess saraswathy, the ultimate veenavadhini  appeared in the dream blessed and gave a mantroupadesha to him which is sure to have bestowed with such expectational veena playing skills. This continued as Sri Raghavendra Teertharu practiced and performed playing Veena intensely to please the Lord. These avatars establish the element of music deeply rooted in the soul. 

The music is the common factors of all these avatars.