Actually, in other Beth games (notably Fallout) if you use the console, achievements are disabled until you restart the game. i still can't figure out a reason they disabled them. it isn't like one could enable them by accident. it takes perseverance. Especially considering you have to do it each time you start up the game
But this isn't a Beth game, this is an id game. I don't think they're worried about accidentally enabling cheats.
How to reenable locked cvars:
Add this to your rageconfig.cfg file:
cvaradd s_lockListener -1; seta s_lockListener 0;
Are you sure? s_ prefix is generally for variables pertaining to the sound system.