I have a feature suggestion... For those of us who use E-APO with headphones, a dedicated crossfeed would be nice. The Bauer Stereo to Binaural DSP plugin for Foobar and Aimp/Winamp, available here - http://bs2b.sourceforge.net/ - works well in Aimp, but it isn't a system wide solution.
I can approximate that filter with a complex series of E-APO commands, but it's not quite the same.
I use E-APO to compensate for some high frequency hearing loss in my right ear, which has allowed me to start enjoying headphones for the first time in my life. Thanks for all you've done. Regarding music, E-APO has literally changed my life. I now own two expensive sets of headphones, and a nice headphone amp, and enjoy them daily, thanks to E-APO.