This is a known bug in the new feature "Ungroup Remembers Layer".
Turn it off by unchecking the option in the Layers panel before ungrouping.
The ungrouped objects are moved to the spread where they were once grouped together.
Had the same problem, thanks sooooo very much for clearing that up. Was driving me nuts.
Glad I found this, it has been driving me NUTS! I hope they fix it soon. Thanks
This has helped me too.
I started getting what I believe the same problem only in CC 2015. One unlocked layer on top with two objects grouped and a second layer underneath that is locked. Ungrouping the two objects makes them jump to the locked layer.
I think (did not test this), you see something differntly.
Indeed the feature where objects remember their layers after ungrouping at work.
The jumping to the locked layer could be forced, because the ungrouped objects remember the layer where they were positioned before grouping.
The bug where ungrouped objects move back to the spread where they were grouped once is resolved in InDesign CC-2015.
Now I had a chance to test the behaviour of "Ungroup Remembers Layer" with two layers where layer one is locked and layer two is unlocked.
It seems "normal" (I admit, it's a bit strange), that all objects in a group that are once grouped on layer one will be moved to layer one back again after ungroping the group on layer two.
At least I waited for a message popping up, telling me, that ungrouping is not possible, because all or some objects would be moved to a locked layer.
And the strange thing is: In the moment when the objects are moved to the locked layer, the objects are still selected. So you could apply fill colors or do something else to the selection.
As soon this selection is deselected, the objects are locked due to the locked state of the layer.
Hm, I think, I can get used to this.
Or do you think, this is an entirely bad thing and should be changed in future versions of InDesign?
The thing about what i am seeing is that the grouped objects on the unlocked layer were only ever on that layer. The locked layer below contains a single photoshop file that is never modified in ID. The objects were either pasted in as vector shapes or placed in the top layer and then grouped. I have a second similar document that is also used as a template with the same objects copied over from the first and they stay on the same layer when ungrouped.