diff --git a/lib/streamaggr/dedup.go b/lib/streamaggr/dedup.go
index 24dcca554..5e8babc5a 100644
--- a/lib/streamaggr/dedup.go
+++ b/lib/streamaggr/dedup.go
@@ -227,6 +227,7 @@ func (das *dedupAggrShard) flush(ctx *dedupFlushCtx, f aggrPushFunc) {
 
 	var m map[string]*dedupAggrSample
 	if len(das.state) == 0 {
+		das.mu.Unlock()
 		return
 	}
 	state := das.state[ctx.dedupIdx]
diff --git a/lib/streamaggr/streamaggr.go b/lib/streamaggr/streamaggr.go
index 422c678bf..dbd44b8c5 100644
--- a/lib/streamaggr/streamaggr.go
+++ b/lib/streamaggr/streamaggr.go
@@ -571,7 +571,6 @@ func newAggregator(cfg *Config, path string, pushFunc PushFunc, ms *metrics.Set,
 	if name == "" {
 		name = "none"
 	}
-	metricLabels := fmt.Sprintf(`name=%q,path=%q,url=%q,position="%d"`, name, path, alias, aggrID)
 
 	// initialize aggrOutputs
 	if len(cfg.Outputs) == 0 {
@@ -579,9 +578,8 @@ func newAggregator(cfg *Config, path string, pushFunc PushFunc, ms *metrics.Set,
 			"see https://docs.victoriametrics.com/stream-aggregation/", supportedOutputs)
 	}
 	aggrOutputs := &aggrOutputs{
-		initFns:       make([]aggrValuesFn, len(cfg.Outputs)),
-		outputSamples: ms.NewCounter(fmt.Sprintf(`vm_streamaggr_output_samples_total{outputs=%q,%s}`, "test", metricLabels)),
-		stateSize:     stateSize,
+		initFns:   make([]aggrValuesFn, len(cfg.Outputs)),
+		stateSize: stateSize,
 	}
 	outputsSeen := make(map[string]struct{}, len(cfg.Outputs))
 	for i, output := range cfg.Outputs {
@@ -591,6 +589,12 @@ func newAggregator(cfg *Config, path string, pushFunc PushFunc, ms *metrics.Set,
 		}
 		aggrOutputs.initFns[i] = oc
 	}
+	outputsLabels := make([]string, 0, len(outputsSeen))
+	for o := range outputsSeen {
+		outputsLabels = append(outputsLabels, o)
+	}
+	metricLabels := fmt.Sprintf(`outputs=%q,name=%q,path=%q,url=%q,position="%d"`, strings.Join(outputsLabels, ","), name, path, alias, aggrID)
+	aggrOutputs.outputSamples = ms.NewCounter(fmt.Sprintf(`vm_streamaggr_output_samples_total{%s}`, metricLabels))
 
 	// initialize suffix to add to metric names after aggregation
 	suffix := ":" + cfg.Interval
@@ -755,11 +759,14 @@ func newOutputInitFns(output string, outputsSeen map[string]struct{}, ignoreFirs
 }
 
 func (a *aggregator) runFlusher(pushFunc PushFunc, alignFlushToInterval, skipIncompleteFlush bool, ignoreFirstIntervals int) {
+	flushDeadline := time.Now().Add(a.interval)
 	alignedSleep := func(d time.Duration) {
 		if !alignFlushToInterval {
 			return
 		}
-
+		if flushDeadline != flushDeadline.Truncate(d) {
+			flushDeadline = flushDeadline.Truncate(d).Add(d)
+		}
 		ct := time.Duration(time.Now().UnixNano())
 		dSleep := d - (ct % d)
 		timer := timerpool.Get(dSleep)
@@ -770,18 +777,26 @@ func (a *aggregator) runFlusher(pushFunc PushFunc, alignFlushToInterval, skipInc
 		}
 	}
 
+	var dedupTime time.Time
+	truncateIfNeeded := func(t time.Time) time.Time {
+		if alignFlushToInterval {
+			return t.Truncate(a.interval)
+		}
+		return t
+	}
 	tickerWait := func(t *time.Ticker) bool {
 		select {
 		case <-a.stopCh:
+			dedupTime = time.Now()
 			return false
-		case <-t.C:
+		case ct := <-t.C:
+			dedupTime = ct
 			return true
 		}
 	}
 
-	flushDeadline := time.Now().Truncate(a.interval).Add(a.interval)
 	tickInterval := time.Duration(a.tickInterval) * time.Millisecond
-	alignedSleep(tickInterval)
+	alignedSleep(a.interval)
 
 	var dedupIdx, flushIdx int
 
@@ -790,11 +805,9 @@ func (a *aggregator) runFlusher(pushFunc PushFunc, alignFlushToInterval, skipInc
 
 	isSkippedFirstFlush := false
 	for tickerWait(t) {
-		ct := time.Now()
-
-		dedupTime := ct.Truncate(tickInterval)
+		dedupDeadline := truncateIfNeeded(dedupTime)
 		if a.ignoreOldSamples {
-			dedupIdx, flushIdx = a.getAggrIdxs(dedupTime, flushDeadline)
+			dedupIdx, flushIdx = a.getAggrIdxs(dedupDeadline, flushDeadline)
 		}
 		pf := pushFunc
 
@@ -813,10 +826,10 @@ func (a *aggregator) runFlusher(pushFunc PushFunc, alignFlushToInterval, skipInc
 			time.Sleep(flushAfter)
 		}
 
-		deleteDeadline := dedupTime.Add(a.stalenessInterval)
+		deleteDeadline := dedupDeadline.Add(a.stalenessInterval)
 		a.dedupFlush(deleteDeadline.UnixMilli(), dedupIdx, flushIdx)
 
-		if ct.After(flushDeadline) {
+		if dedupTime.After(flushDeadline) {
 			// It is time to flush the aggregated state
 			if alignFlushToInterval && skipIncompleteFlush && !isSkippedFirstFlush {
 				a.flush(nil, 0, flushIdx)
@@ -827,7 +840,7 @@ func (a *aggregator) runFlusher(pushFunc PushFunc, alignFlushToInterval, skipInc
 			} else {
 				a.flush(pf, flushDeadline.UnixMilli(), flushIdx)
 			}
-			for ct.After(flushDeadline) {
+			for dedupTime.After(flushDeadline) {
 				flushDeadline = flushDeadline.Add(a.interval)
 			}
 		}
@@ -840,10 +853,10 @@ func (a *aggregator) runFlusher(pushFunc PushFunc, alignFlushToInterval, skipInc
 	}
 
 	if !skipIncompleteFlush && ignoreFirstIntervals <= 0 {
-		dedupTime := time.Now().Truncate(tickInterval).Add(tickInterval)
+		dedupDeadline := truncateIfNeeded(dedupTime)
 		deleteDeadline := flushDeadline.Add(a.stalenessInterval)
 		if a.ignoreOldSamples {
-			dedupIdx, flushIdx = a.getAggrIdxs(dedupTime, flushDeadline)
+			dedupIdx, flushIdx = a.getAggrIdxs(dedupDeadline, flushDeadline)
 		}
 		a.dedupFlush(deleteDeadline.UnixMilli(), dedupIdx, flushIdx)
 		a.flush(pushFunc, flushDeadline.UnixMilli(), flushIdx)