diff --git a/core/internal/server/wayland/manager.go b/core/internal/server/wayland/manager.go
index 62a9f2b7..0d2d047a 100644
--- a/core/internal/server/wayland/manager.go
+++ b/core/internal/server/wayland/manager.go
@@ -103,18 +103,16 @@ func (m *Manager) waylandActor() {
 	}
 }
 
-func (m *Manager) allOutputsReady() bool {
-	hasOutputs := false
-	allReady := true
+func (m *Manager) anyOutputReady() bool {
+	anyReady := false
 	m.outputs.Range(func(_ uint32, out *outputState) bool {
-		hasOutputs = true
-		if out.rampSize == 0 || out.failed {
-			allReady = false
-			return false
+		if out.rampSize > 0 && !out.failed {
+			anyReady = true
+			return false // stop iteration
 		}
 		return true
 	})
-	return hasOutputs && allReady
+	return anyReady
 }
 
 func (m *Manager) setupDBusMonitor() error {
@@ -278,7 +276,8 @@ func (m *Manager) setupControlHandlers(state *outputState, control *wlr_gamma_co
 				out.failed = false
 				out.retryCount = 0
 			}
-			m.applyCurrentTemp()
+			m.lastAppliedTemp = 0
+			m.applyCurrentTemp("gamma_size")
 		})
 	})
 
@@ -528,8 +527,9 @@ func (m *Manager) getNextDeadline(now time.Time) time.Time {
 		return m.tomorrow(now)
 	case StateNormal:
 		return m.getDeadlineNormal(now, sched)
+	default:
+		return m.tomorrow(now)
 	}
-	return m.tomorrow(now)
 }
 
 func (m *Manager) getDeadlineNormal(now time.Time, sched sunSchedule) time.Time {
@@ -588,7 +588,7 @@ func (m *Manager) schedulerLoop() {
 	m.configMutex.RUnlock()
 
 	if enabled {
-		m.post(func() { m.applyCurrentTemp() })
+		m.post(func() { m.applyCurrentTemp("startup") })
 	}
 
 	var timer *time.Timer
@@ -630,24 +630,27 @@ func (m *Manager) schedulerLoop() {
 			enabled := m.config.Enabled
 			m.configMutex.RUnlock()
 			if enabled {
-				m.post(func() { m.applyCurrentTemp() })
+				m.post(func() { m.applyCurrentTemp("updateTrigger") })
 			}
 		case <-timer.C:
 			m.configMutex.RLock()
 			enabled := m.config.Enabled
 			m.configMutex.RUnlock()
 			if enabled {
-				m.post(func() { m.applyCurrentTemp() })
+				m.post(func() { m.applyCurrentTemp("timer") })
 			}
 		}
 	}
 }
 
-func (m *Manager) applyCurrentTemp() {
-	if !m.controlsInitialized || !m.allOutputsReady() {
+func (m *Manager) applyCurrentTemp(_ string) {
+	if !m.controlsInitialized || !m.anyOutputReady() {
 		return
 	}
 
+	// Ensure schedule is up-to-date (handles display wake after overnight sleep)
+	m.recalcSchedule(time.Now())
+
 	m.configMutex.RLock()
 	low, high := m.config.LowTemp, m.config.HighTemp
 	m.configMutex.RUnlock()
@@ -680,6 +683,10 @@ func (m *Manager) applyGamma(temp int) {
 		return
 	}
 
+	if m.lastAppliedTemp == temp && m.lastAppliedGamma == gamma {
+		return
+	}
+
 	var outs []*outputState
 	m.outputs.Range(func(_ uint32, out *outputState) bool {
 		outs = append(outs, out)
@@ -715,6 +722,7 @@ func (m *Manager) applyGamma(temp int) {
 
 	for _, j := range jobs {
 		if err := m.setGammaBytes(j.out, j.data); err != nil {
+			log.Warnf("gamma: failed to set output %d: %v", j.out.id, err)
 			j.out.failed = true
 			j.out.rampSize = 0
 			outID := j.out.id
@@ -727,6 +735,9 @@ func (m *Manager) applyGamma(temp int) {
 			})
 		}
 	}
+
+	m.lastAppliedTemp = temp
+	m.lastAppliedGamma = gamma
 }
 
 func (m *Manager) setGammaBytes(out *outputState, data []byte) error {
@@ -901,6 +912,10 @@ func (m *Manager) SetConfig(config Config) error {
 
 func (m *Manager) SetTemperature(low, high int) error {
 	m.configMutex.Lock()
+	if m.config.LowTemp == low && m.config.HighTemp == high {
+		m.configMutex.Unlock()
+		return nil
+	}
 	m.config.LowTemp = low
 	m.config.HighTemp = high
 	err := m.config.Validate()
@@ -914,6 +929,11 @@ func (m *Manager) SetTemperature(low, high int) error {
 
 func (m *Manager) SetLocation(lat, lon float64) error {
 	m.configMutex.Lock()
+	if m.config.Latitude != nil && m.config.Longitude != nil &&
+		*m.config.Latitude == lat && *m.config.Longitude == lon && !m.config.UseIPLocation {
+		m.configMutex.Unlock()
+		return nil
+	}
 	m.config.Latitude = &lat
 	m.config.Longitude = &lon
 	m.config.UseIPLocation = false
@@ -928,6 +948,10 @@ func (m *Manager) SetLocation(lat, lon float64) error {
 
 func (m *Manager) SetUseIPLocation(use bool) {
 	m.configMutex.Lock()
+	if m.config.UseIPLocation == use {
+		m.configMutex.Unlock()
+		return
+	}
 	m.config.UseIPLocation = use
 	if use {
 		m.config.Latitude = nil
@@ -946,6 +970,12 @@ func (m *Manager) SetUseIPLocation(use bool) {
 
 func (m *Manager) SetManualTimes(sunrise, sunset time.Time) error {
 	m.configMutex.Lock()
+	if m.config.ManualSunrise != nil && m.config.ManualSunset != nil &&
+		m.config.ManualSunrise.Hour() == sunrise.Hour() && m.config.ManualSunrise.Minute() == sunrise.Minute() &&
+		m.config.ManualSunset.Hour() == sunset.Hour() && m.config.ManualSunset.Minute() == sunset.Minute() {
+		m.configMutex.Unlock()
+		return nil
+	}
 	m.config.ManualSunrise = &sunrise
 	m.config.ManualSunset = &sunset
 	err := m.config.Validate()
@@ -959,6 +989,10 @@ func (m *Manager) SetManualTimes(sunrise, sunset time.Time) error {
 
 func (m *Manager) ClearManualTimes() {
 	m.configMutex.Lock()
+	if m.config.ManualSunrise == nil && m.config.ManualSunset == nil {
+		m.configMutex.Unlock()
+		return
+	}
 	m.config.ManualSunrise = nil
 	m.config.ManualSunset = nil
 	m.configMutex.Unlock()
@@ -967,6 +1001,10 @@ func (m *Manager) ClearManualTimes() {
 
 func (m *Manager) SetGamma(gamma float64) error {
 	m.configMutex.Lock()
+	if m.config.Gamma == gamma {
+		m.configMutex.Unlock()
+		return nil
+	}
 	m.config.Gamma = gamma
 	err := m.config.Validate()
 	m.configMutex.Unlock()
@@ -980,6 +1018,10 @@ func (m *Manager) SetGamma(gamma float64) error {
 func (m *Manager) SetEnabled(enabled bool) {
 	m.configMutex.Lock()
 	wasEnabled := m.config.Enabled
+	if wasEnabled == enabled {
+		m.configMutex.Unlock()
+		return
+	}
 	m.config.Enabled = enabled
 	highTemp := m.config.HighTemp
 	m.configMutex.Unlock()
@@ -989,7 +1031,7 @@ func (m *Manager) SetEnabled(enabled bool) {
 		m.post(func() {
 			gammaMgr := m.gammaControl.(*wlr_gamma_control.ZwlrGammaControlManagerV1)
 			if err := m.setupOutputControls(m.availableOutputs, gammaMgr); err != nil {
-				log.Errorf("Failed to create gamma controls: %v", err)
+				log.Errorf("gamma: failed to create controls: %v", err)
 				return
 			}
 			m.controlsInitialized = true
diff --git a/core/internal/server/wayland/types.go b/core/internal/server/wayland/types.go
index d7e2bd0b..44861bdd 100644
--- a/core/internal/server/wayland/types.go
+++ b/core/internal/server/wayland/types.go
@@ -96,6 +96,9 @@ type Manager struct {
 
 	dbusConn   *dbus.Conn
 	dbusSignal chan *dbus.Signal
+
+	lastAppliedTemp  int
+	lastAppliedGamma float64
 }
 
 type outputState struct {