Photoshop: Alt-Drag with duplicate modify for Multiple Layers not duplicating all layers

using the alt-drag duplicate feature for multiple layers sometimes deselects a layer or two upon dragging, causing one or more of the layers to not be duplicated. i am using the latest version of Photoshop CC
EDIT: I should also add that this happens with 4 layers, and i am starting out holding shift before i alt-drag to keep the items aligned to an axis