The brain works on template systems with the perception of senses and patterns. When something is close to the template the mind doesn’t notice a difference. When it varies greatly from the template, the brain either assimilates, accommodates, and/or integrates it with its current template. I think it’s fairly normal brain functioning for someone to “eq” the sound from any reasonable audio source over time. The brain noticing perceptions far outside the usual parameters is evolutionary and useful for survival, and being able to integrate those differences over time is useful when the changes aren’t threatening.