I'm away from my books right now but can't resist taking a guess. First, it looks like a woodpecker, but a very small one. I know some of these are called Piculets. As to the species, l'll sleep on it.
Ochre-collared Piculet perhaps? I put "piculet" into google and a very close match came up for that species. Take a look and see what you think. Kudos to John for knowing it was Piculet.
I had a look at reference for southern South America- De La Peņa and Rumboll, and the species mentioned by Matt and Paul are the candidates for sure. However, I think we can see enough of the nape to say that it's a White-barred Piculet rather than the Ochre-collared.
Nice bird by the way! I'm very envious of Adams to be seeing species like this on a regular basis.