[2021] Can't hear Wraith's Breathing? (Is Hacking in DBD that rampant?)

It might be a sound bug potentially, not necessarily hacking. If you do assume hacking, you need to report it and send a ticket to support.

However, as it might be a sound bug, I'd suggest reporting it here first, as we do not have a bug sub-forum on Steam: https://forum.deadbydaylight.com/en/categories/bugs