Turn audio soft mixing into an opt-in toggle

It causes issues on some machines, but is required on the Asus G14

config/wireplumber/wireplumber.conf.d/alsa-soft-mixer.conf

@@ -1,18 +0,0 @@
-## Use software volume control for all ALSA devices.
-## This prevents hardware mixer quirks (like muffled audio on Realtek codecs)
-## and provides consistent volume behavior across all hardware.
-
-monitor.alsa.rules = [
-  {
-    matches = [
-      {
-        device.name = "~alsa_card.*"
-      }
-    ]
-    actions = {
-      update-props = {
-        api.alsa.soft-mixer = true
-      }
-    }
-  }
-]