Made a discovery. i set the detection to everything and add the "Player" tag it mostly works, except i have to get decently close for the AI to hear me. i tried increasing range and also playing with audible threshold. but i don't know exactly what numbers for audible threshold are good. i noticed if i set audible threshold to 0 the player is instantly heard once inside the range.
*update noticed that if i play with the min and max dist in sound section, the enemy seems to hear me better??
umm i am confused
For your first issue Can Hear Object doesn't recurse the GameObjects so when you have a target set to CowsinsFPSController it's not going to find the AudioSource on the Player GameObject. If you change the target it should then read the Audio Source correctly.
In terms of the threshold the best that I've found is the just subtly adjust the values until you get one that works.