I tried Supercrunch, I couldn't hear the enemy.
I can hear my teammates footsteps, just not the enemies until I used Awareness.
Yes, I think awareness is a no brainer. Out off all the in game audio settings 'Supercrunch' has the least bass, which = best for hearing footsteps and other enemy animation related audio, such as gun reloads and grenade pins being pulled, or landing near you.
Also, (its going to sound condescending) have you checked all your cables are working correctly and fully connected? Sometimes you can have an audio jack that isn't inserted properly, and you loose certain frequency's. Worth a check, I was using a £1 USB sound card with some PC360s and could hear a mouse fart on the other side of the map.