Zhonya's Bug

At IEM, during the C9 and YFW match, Hai used Zhonya's Hourglass during a fight. It kept on ringing until he used his Zhonya's again and during the replay. Also, there was a glowy part of Zhonya's on Lissandra's crown, which can be found at 45:20, that also kept ringing until the next activation. By the way, it was heard all over the map.

EDIT: There is a bit of a prelude, sorry didn't realize. Go to 43:40 if not interested in the whole fight.