diff --git a/homeassistant/components/sonos/__init__.py b/homeassistant/components/sonos/__init__.py
index 57aed48c466..e7e0b3952eb 100644
--- a/homeassistant/components/sonos/__init__.py
+++ b/homeassistant/components/sonos/__init__.py
@@ -298,6 +298,8 @@ class SonosDiscoveryManager:
         def _add_speakers():
             """Add all speakers in a single executor job."""
             for soco in socos:
+                if soco.uid in self.data.discovered:
+                    continue
                 sub = None
                 if soco.uid == zgs_subscription_uid and zgs_subscription:
                     sub = zgs_subscription