Normally this is expressed as a short noise or popping, loud buzz (rare), or the very beginning of whatever audio stream is replacing said sound buffer.

Easy way to trigger the last one is by playing any cutscene that gives you an item at the end (such as fortress-blow-up-ammo-res-a which gives red pass or city-keira-delivery-intro which gives green pass) since miss006/miss007 (why are there so many of these?) is played right after.