In the following two verses spoken to Śrī Vedavyāsa, Śrī Nārada clearly refers to Kṛṣṇa:

I wander all over singing the līlās of Śrī Hari [Kṛṣṇa] while playing on this vīṇā instrument, which was given to me by the effulgent Lord (deva-datta) and is adorned with the [seven] musical notes that embody Brahman in the form of sound. When I sing of the heroic deeds of the Lord whose glory is most endearing and whose feet are the source of all holy places, He quickly appears in my heart as if summoned by me. (SB 1.6.33–34) exclusively upon Śrī Kṛṣṇa.

“The effulgent Lord” (deva) can refer only to Śrī Kṛṣṇa, as it is well-known from the upari-bhāga of the Liṅga Purāṇa that it is He who personally gave the vīṇā to Nārada. From the congruity of meaning, it naturally follows that the form of the Lord that appeared in Nārada’s heart is exactly that in which He gave him the vīṇā. Remembering the gift of the vīṇā bestowed upon him by Śrī Kṛṣṇa, Nārada used the compound deva-datta, “given by the effulgent Lord,” specifically out of the deliberation on Him.