It may be a Speckled Piculet, which does have a very high-pitched call like this. Although I'm not entirely sure that it isn't an insect of some sort. Author: yann_in_tokyo Time: 17/08/2017 22:37
I'd say Chestnut-crowned Warbler. Sounds like a bird to me. Did you record directly with a smartphone ? Author: cgeoff Time: 18/08/2017 10:21
Not Pygmy Wren Babbler, I feel sure.
It doesn't feel right for Chestnut-crowned to me. Nor Speckled Piculet for that matter. As John says, I wouldn't be surprised if it's an insect.
GeoffC
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