shaco + gift of heavy hands

gift of heavy hands (from smiting the rock) will actually STUN if he has the buff and uses his ult after 5.5 patch. This has happened multiple times and has royally screwed me, I see the effect and i cannot move and nobody else had the buff but me, EVERY time

this has happened multiple times and i thought i was just laggin until i noticed no one else lagging, the debuff on my champion visually, and flat out being stunned, also stuns my clone at the same time.

edit: Seems i can't replicate trying it alone but it's still happened multiple times to me in a few games. Not sure if there is something else taking place or not