Komentarz do Diwrej ha-jamim II 9:11

a path מְסִלּוֹת, stairs. In I Kings (10:12) it is written מִסְעָד, [a support] after the manner that they make for those who ascend by way of elevated places and stairs. Some say that מִסְעָד and מְסִילָה are one and the same.

and harps and psalteries for the singers Some say (Jonathan and Rashi to Kings) for the Levites who sing with musical instruments, and Rabbi Eliezer explained it to mean: for the singers who stroll before the king. A similar case is (I Kings 5:12): “and his songs were a thousand and five.” These were secular songs that he composed to sing before him, and that is what is meant (below 35:25): “And Jeremiah lamented over Josiah, and all the male singers and the female singers recited in their lamentations, etc.”