Some weeks ago I enabled the EQ on my RME TotalMix software to notch out some nasty frequencies in the voice of a YouTube Tutorial I was watching. I also enabled a HPF at around 80Hz to roll off the rumble in the audio.
Well after I'd watched the video I toggled the little EQ button off and forgot about it, thinking that I'd disabled all EQ processing. Just recently I started to suspect that music I was listening to on my cans didn't have as much oomph as it used to, and some of my own mixes were sounding a little weak through them. Tonight it just dawned on me that there is a SEPARATE toggle for the HPF and that I've had that HPF rolling off 80Hz and lower through my headphones for the last few weeks. How ridiculous is that?