Simply wondering if you can turn the perk on/off somewhere. I like the idea of quiet spell-casting when I'm sneaking about - but not being about to relish my might in full surround sound when sending exploding fireballs or bolts of lightning at my enemies would detract from the experience I think.

Anyone know?

Perhaps they still emit sound that only you can hear. Thus the sound effects aren't gone, but your surrounding just won't react to it.