AE does not have realtime audio playback. You can kinda scrub through audio by holding down Ctrl, but that's all. Otherwise you have to use audio/ RAM previews, which obey the settings on the preview palette and the work area, which I think is the part you haven't figured out.
So there is a way to only render the RAM preview in the work area in stead of the whole 5 minutes?
and if so, how can i access it?
The best way to do what you are trying to do is to open up Premiere Pro and do speech recognition on the audio track then import the audio into After Effects and you'll have labeled markers for every word exactly in the right place. If you create a transcript of the words then your speech recognition will be perfect. I work this way all the time.
The alternative to that is to press the . key to run an audio preview and then use the * key on the numeric keypad to set markers on the audio track.