4Game

: check if you use some kind of loudness equalizer ( windows has that feature) it makes every sound the same volume. While it makes gunshots quieter it makes rain and ambient louder. Also it reduces your ability of guessing sound distances, or if somebody is running towards you or away from you, footsteps don't get louder or quieter with that feature. Better is to limit the max volume using sound lock.

Check if any software / driver ads any kind of surround effect or something ( make shure that in windows settings 'mono' option is not selected. )

The game only delivers stereo.

There is an in game setting ' binaural sound '( google that term)
It applies filters from sounds directly in front and back to distinguish those. And plays sounds from left stereo on the right ear with a slightest delay and quieter to simulate like your ears work irl. ( may costs performance because it's taxing on the cpu)

Takes some getting used to.

I like it but some don't.

Without binaural sound i used to turn my head a lot to pinpoint sounds.

Use the in game headsets, they increase hearing. Check YouTube comparisons for those. Which headset is best for you depends on your irl headphones and your taste.

Make sure to use sound lock to protect your hearing.

In game there is a skill called 'perception ' it determines the hearing distance.

At the end of the day also the hardware could be bad. Soundcard and headphones.
Especially good irl headphones made a big difference for me.