Casey Kasem

From Loonipedia

Kemal Amin "Casey" Kasem (born on April 27th, 1932) is an American radio personality and voice-actor, best known as the original voice of Shaggy Rogers from the popular Scooby-Doo franchise.

For Looney Tunes, he voiced Flakey Flakems (an obvious spoof of himself) in Tiny Toon Adventures.