What's the Extent of a Kenku's Mimicry?

[ArcanaCapra]

Mimicry. You can mimic sounds you have heard, including
voices. A creature that hears the sounds you make can tell
they are imitations with a successful Wisdom (Insight) check
opposed by your Charisma (Deception) check.

So, what's the extent of this trait?

Say a kenku listens to a band performing at a tavern, playing flute, violin, drums and whatnot. Would it be able to replicate the music, making the sound of multiple instruments at the same time, or would it only be able to mimic one of the instruments at once?

In other words, can a kenku act as an organic audio recorder and mimic sounds with multiple sources (such as a band playing) or can they only mimic sounds with one source (such as a single instrument/voice)?

[AchuakScale]

I would rule it as a single source only. However, I would also rule that listening to the band might allow the Kenku to mimic those sounds heard, just not all at once.

[Rukelnikov]

I'd rule it as so, the price you are paying is exceedengly high, so it warrants being able to do stuff like that. At most make it an intelligence check to remember every detail.