Spend a few minutes in a completely silent room and you start noticing sounds inside your own body, your breathing, your heartbeat. That's not a coincidence, your brain expects a steady stream of input, and when there's none, it amplifies whatever low-level signal it can find.
That's why total silence doesn't feel restful to some people, it feels like being on alert. With no reference point in the room, the mind starts perceiving even the smallest sound as exaggerated.
The fix isn't removing silence entirely, it's adding one very light, steady layer of sound underneath it. That stops the brain from constantly asking “what was that” and softens the part of silence that feels uncomfortable.