I don't know about songs, but here's a macaronic bit of the poem "Philip Sparrow" by John Skelton, who lived around 1500, and who is the first person the word "macaronic" reminds me of. The poem is about the death of a pet sparrow.

Alas, it will me so
That Philip is gone me fro!
Si in i qui ta tes,
Alas, I was evil at ease!
De pro fun dis cla ma vi
When I saw my sparrow die!