Its existence isn’t settled science, but I have this too and I’ve found that Auditory Processing Disorder describes it perfectly. Lots of comorbidity with autism and ADHD, so it’s possible it’s not a separate disorder but just another manifestation.

But yeah, I can’t filter out background noise at all. My brain copes by completely shutting off audio processing when I’m focusing, but it’s involuntary and can be pretty inconvenient. I have to read lips a lot when talking anywhere but a quiet environment because I can’t separate speech from background noise.