This 2 October 2019 video says about itself:
Male Thick-billed Euphonia Extended Singing Session – Oct 2, 2019
One of the most common visitors to the Panama Fruit Feeder, the Thick-billed Euphonia, is quite a skilled mimic. The Thick-billed Euphonia’s song is a rambling string of original notes and mimicked notes from other birds. Both males and females sing a variety of musical notes including a loud sharp “preet” and harsh, buzzy rattled “tziit”. Listen to this male perform his lovely song for us at the feeder.