Have you loolked at the media player > options > scroll to bottom > headset equalizer?
Okay so you're pulling my chain. I get it. There is no equalizer. I guess it was a dumb question. But no third party apps to do this I guess? I'm new to Blackberry so don't know what to expect or not expect from RIM.
Related to this thread... Will I loose everything I have on my BB when I upgrade to the next OS? I'd go ahead with a beta if I knew I wouldn't loose all my apps and data.