diff --git a/ts/state/ducks/calling.ts b/ts/state/ducks/calling.ts
index 4c557c333c36..f127404915e9 100644
--- a/ts/state/ducks/calling.ts
+++ b/ts/state/ducks/calling.ts
@@ -76,7 +76,11 @@ import { ToastType } from '../../types/Toast';
 import type { ShowToastActionType } from './toast';
 import type { BoundActionCreatorsMapObject } from '../../hooks/useBoundActions';
 import { useBoundActions } from '../../hooks/useBoundActions';
-import { isAnybodyElseInGroupCall } from './callingHelpers';
+import {
+  isAnybodyElseInGroupCall,
+  isAnybodyInGroupCall,
+  MAX_CALL_PARTICIPANTS_FOR_DEFAULT_MUTE,
+} from './callingHelpers';
 import { SafetyNumberChangeSource } from '../../components/SafetyNumberChangeDialog';
 import {
   isGroupOrAdhocCallMode,
@@ -2215,7 +2219,8 @@ const _startCallLinkLobby = async ({
   const callLobbyData = await calling.startCallLinkLobby({
     callLinkRootKey,
     adminPasskey,
-    hasLocalAudio: groupCallDeviceCount < 8,
+    hasLocalAudio:
+      groupCallDeviceCount < MAX_CALL_PARTICIPANTS_FOR_DEFAULT_MUTE,
   });
   if (!callLobbyData) {
     return;
@@ -2314,7 +2319,8 @@ function startCallingLobby({
 
     const callLobbyData = await calling.startCallingLobby({
       conversation,
-      hasLocalAudio: groupCallDeviceCount < 8,
+      hasLocalAudio:
+        groupCallDeviceCount < MAX_CALL_PARTICIPANTS_FOR_DEFAULT_MUTE,
       hasLocalVideo: isVideoCall,
     });
     if (!callLobbyData) {
@@ -3114,6 +3120,17 @@ export function reducer(
               hasLocalAudio,
               hasLocalVideo,
             };
+
+      // The first time we detect call participants in the lobby, check participant count
+      // and mute ourselves if over the threshold.
+      if (
+        joinState === GroupCallJoinState.NotJoined &&
+        !isAnybodyInGroupCall(existingCall?.peekInfo) &&
+        newPeekInfo.deviceCount >= MAX_CALL_PARTICIPANTS_FOR_DEFAULT_MUTE &&
+        newActiveCallState?.hasLocalAudio
+      ) {
+        newActiveCallState.hasLocalAudio = false;
+      }
     } else {
       newActiveCallState = state.activeCallState;
     }
diff --git a/ts/state/ducks/callingHelpers.ts b/ts/state/ducks/callingHelpers.ts
index 1fbc224b58d6..444e80406139 100644
--- a/ts/state/ducks/callingHelpers.ts
+++ b/ts/state/ducks/callingHelpers.ts
@@ -14,6 +14,8 @@ import type {
   GroupCallStateType,
 } from './calling';
 
+export const MAX_CALL_PARTICIPANTS_FOR_DEFAULT_MUTE = 8;
+
 // In theory, there could be multiple incoming calls, or an incoming call while there's
 //   an active call. In practice, the UI is not ready for this, and RingRTC doesn't
 //   support it for direct calls.
diff --git a/ts/test-electron/state/ducks/calling_test.ts b/ts/test-electron/state/ducks/calling_test.ts
index 488f0f29d5b4..1749e41abfd2 100644
--- a/ts/test-electron/state/ducks/calling_test.ts
+++ b/ts/test-electron/state/ducks/calling_test.ts
@@ -137,6 +137,28 @@ describe('calling duck', () => {
     },
   };
 
+  const stateWithNotJoinedGroupCall: CallingStateType = {
+    ...getEmptyState(),
+    callsByConversation: {
+      'fake-group-call-conversation-id': {
+        callMode: CallMode.Group,
+        conversationId: 'fake-group-call-conversation-id',
+        connectionState: GroupCallConnectionState.NotConnected,
+        joinState: GroupCallJoinState.NotJoined,
+        localDemuxId: 1,
+        peekInfo: {
+          acis: [],
+          pendingAcis: [],
+          creatorAci,
+          eraId: 'xyz',
+          maxDevices: 16,
+          deviceCount: 0,
+        },
+        remoteParticipants: [],
+      } satisfies GroupCallStateType,
+    },
+  };
+
   const stateWithIncomingGroupCall: CallingStateType = {
     ...stateWithGroupCall,
     callsByConversation: {
@@ -151,21 +173,23 @@ describe('calling duck', () => {
     },
   };
 
+  const groupCallActiveCallState: ActiveCallStateType = {
+    callMode: CallMode.Group,
+    conversationId: 'fake-group-call-conversation-id',
+    hasLocalAudio: true,
+    hasLocalVideo: false,
+    localAudioLevel: 0,
+    viewMode: CallViewMode.Paginated,
+    showParticipantsList: false,
+    outgoingRing: false,
+    pip: false,
+    settingsDialogOpen: false,
+    joinedAt: null,
+  };
+
   const stateWithActiveGroupCall: CallingStateTypeWithActiveCall = {
     ...stateWithGroupCall,
-    activeCallState: {
-      callMode: CallMode.Group,
-      conversationId: 'fake-group-call-conversation-id',
-      hasLocalAudio: true,
-      hasLocalVideo: false,
-      localAudioLevel: 0,
-      viewMode: CallViewMode.Paginated,
-      showParticipantsList: false,
-      outgoingRing: false,
-      pip: false,
-      settingsDialogOpen: false,
-      joinedAt: null,
-    },
+    activeCallState: groupCallActiveCallState,
   };
 
   const ourAci = generateAci();
@@ -1319,6 +1343,84 @@ describe('calling duck', () => {
 
         assert.isFalse(result.activeCallState?.outgoingRing);
       });
+
+      it('mutes self in lobby when getting peek info with a lot of devices', () => {
+        const result = reducer(
+          {
+            ...stateWithNotJoinedGroupCall,
+            activeCallState: groupCallActiveCallState,
+          },
+          getAction({
+            callMode: CallMode.Group,
+            conversationId: 'fake-group-call-conversation-id',
+            connectionState: GroupCallConnectionState.Connecting,
+            joinState: GroupCallJoinState.NotJoined,
+            localDemuxId: 1,
+            hasLocalAudio: true,
+            hasLocalVideo: true,
+            peekInfo: {
+              acis: Array(20).map(generateAci),
+              pendingAcis: [],
+              maxDevices: 16,
+              deviceCount: 20,
+            },
+            remoteParticipants: [],
+          })
+        );
+
+        assert.isFalse(result.activeCallState?.hasLocalAudio);
+      });
+
+      it('does not mute self when getting peek info with few devices', () => {
+        const result = reducer(
+          {
+            ...stateWithNotJoinedGroupCall,
+            activeCallState: groupCallActiveCallState,
+          },
+          getAction({
+            callMode: CallMode.Group,
+            conversationId: 'fake-group-call-conversation-id',
+            connectionState: GroupCallConnectionState.Connecting,
+            joinState: GroupCallJoinState.NotJoined,
+            localDemuxId: 1,
+            hasLocalAudio: true,
+            hasLocalVideo: true,
+            peekInfo: {
+              acis: [ACI_1],
+              pendingAcis: [],
+              maxDevices: 16,
+              deviceCount: 1,
+            },
+            remoteParticipants: [],
+          })
+        );
+
+        assert.isTrue(result.activeCallState?.hasLocalAudio);
+      });
+
+      it('does not mute self when connected with many devices', () => {
+        const result = reducer(
+          stateWithActiveGroupCall,
+          getAction({
+            callMode: CallMode.Group,
+            conversationId: 'fake-group-call-conversation-id',
+            connectionState: GroupCallConnectionState.Connected,
+            joinState: GroupCallJoinState.Joined,
+            localDemuxId: 1,
+            hasLocalAudio: true,
+            hasLocalVideo: true,
+            peekInfo: {
+              acis: Array(20).map(generateAci),
+              pendingAcis: [],
+              maxDevices: 16,
+              deviceCount: 20,
+            },
+            remoteParticipants: [],
+          })
+        );
+
+        assert.isTrue(result.activeCallState?.hasLocalAudio);
+      });
     });
 
     describe('handleCallLinkUpdate', () => {