Since Narada Muni’s ista-devata is Lord Narayana, he himself is always saying, “Narayana, Narayana, Narayana.” However, Padma Purana describes how Narada Muni once became a gopi by tapas, bathing in Vrindavana, and the mercy of Yogamaya. His name became Nardiya Gopi.
Narada Muni has personally often glorified Srimati Radharani and described Her worship in many prayers and verses such as the Radha Sahasranam in Narada Pancharatra. As far as Narada’s VINA CHANTING RADHA nama, the proof is here:
Srila Prabhupada said, “In this regard, Çréla Bhaktivinoda Öhäkura has sung:
närada-muni, bäjäya véëä, ‘rädhikä-ramaëa’-näme, which means, “Narada Muni’s VINA is singing the name Radhika Ramana.” Thus the name of Radha arises from Narada’s vina! Jai Jai Sri Radhe!