The first televised version of ANH in Sweden did seem to have the mono mix, and in that Luke's line "what good will it do us if he gets himself killed? Come on!"sounds different to all other versions I've seen.
In the cell bay shootout Chewie's rifle sounds like the other blasters, except for the last shot we see him shoot, where it's got a stunblast-esque sound to it.
And the blast that nearly hits Leia as she's jumping into the garbage chute is more powerful.