volume effect seems not to be working

Hi I am trying to up the volume and I figured out how to double click in the 'effect list' volume...then i looked in the 'effect stack'. The green tick seemed to indicate that the effect was active but when I used the up and down arrows they didn't make a difference to the audio. I added an avi clip and I am trying to enhance the audio as it is too low. I am new to this program so I am not sure what I am doing.