Nunu missing voice

Playing a game as Nunu with the Nunu bot skin today I realized he wasn't chatting like he normally does. Typically on move, attack, revive, etc. he'll say something (usually about towerdiving) but he was silent. I loaded up a practice game with him and found the same issue, even trying other skins and finding them similarly silenced.

/taunt and /joke still work, but he otherwise does not speak.

I loaded up another champion (pantheon) in practice mode and he spoke normally on move, etc.