I have been observing this hole in the dead teak tree for a few weeks.
This is the view from my back door. The tree is a cross a small stream, about 20 meters from my house.
The same species of birds visited it.
They just looking around, and peek in looking for food. No signs of nesting activity.
Female Flame-back Woodpwecker, looking inside.
Javan Myna goes in deep, inspecting the hole.