When traversing an ARIA combobox, the user sometimes hears "not selected" on items.
See here in the ARIA spec:
https://www.w3.org/TR/wai-aria-1.1/#aria-selected
"Single-selection containers where the currently focused item is not selected. The selection normally follows the focus, and is managed by the user agent."
There is also relevant text in CORE-AAM.
Workaround: set aria-selected="true" on focused item.
Comment 1 by aleventhal@chromium.org
, May 23 2018