I need to translate a sentence from an American comics about super-heros. There's a dialogue and the two are talking about Dr. Druid, who is now dead and had druid powers, such hypnotism and telepathy. One of the two, talking about Dr Druid says: "That guy, man. He knew from a/v hookups.”
I am not really able what this "a/v" term stands for. Therefore it is also difficult to understand the meaning of "hookups" in this context.
Thank you all for your help!