Just noticed this today, but I think I've been experiencing it without realising for a long time.
When using a PS4 controller with vibration turned on, the sound effects and dialog are much more quiet and muffled. Turning off vibration restores the sound levels to normal. Mouse & Keyboard input has no issue.
I'd prefer to play with vibration on but the sound is so much better now, I'll be leaving it off.
I've only been able to find one other player with this issue so I'm not anticipating a fix, but I thought I should let someone know.