Sion's ult audio hidden by fog of war [Gameplay]

Normally when Sion activates his ultimate, there is a sound to notify the map when his ultimate is activated. Currently, when his ultimate is activated, it is reportedly audible for his allied team, but the sound is not audible by the enemy team unless he is visible, outside of the fog of war for the enemy team.

For four of his five ultimates in game, Sion emerged from the fog of war with ultimate activate, but it was not audible for the enemy team. For his fifth ultimate, he activated it outside of the fog of war, and the sound was only audible for all his allies, and members of enemy team who had vision of Sion.

Edit: The game with this bug was in Team Builder.