Hi, I recently bought my mother an iMac 21.5" (Late 2013) base model and she's really happy with it. The only complaint she has is the loud bass from the internal speakers. I took the iMac for a listen and to me the speakers sounded fine, so it's definitely normal. However, the bass gain is high enough to make listening to audio on the iMac difficult to my mother. Is there a system-wide equalizer or tweak that allows adjusting of the bass gain? If not, I might have to buy a pair of cheap PC speakers, which usually have a "tone" knob that cuts off from the lower to higher frequencies. (Which is exactly what I'm looking for, but in software.) Thanks!