Conte led Napoli to the Scudetto last season at first attempt, but he failed to win over Viviano.
"I don't like Conte, in the sense that every time I hear him speak, I don't like him," Viviano said on the podcast, Te ne intendi di calcio.
"I'm not crazy about his football either, but if I say Conte is an idiot, I'm the idiot. Conte is a great coach, a winner, someone who knows how to do things. Then again, if you talk to me, I prefer other coaches.
"And some people, to go against (Max) Allegri, make him look like the absolute idiot, and that bothers me.
"I don't really like what he says either, but he's exaggerating. In terms of communication, he's number one for me; he's won and that's all there is to it, but personally, if I have to watch a team play, I'd rather watch a team that isn't coached by him."