diff --git a/cmd/mxl-sync/main.go b/cmd/mxl-sync/main.go
new file mode 100644
index 0000000..f813009
--- /dev/null
+++ b/cmd/mxl-sync/main.go
@@ -0,0 +1,116 @@
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/qvest-digital/go-mxl/mxl"
+)
+
+func main() {
+	domain := flag.String("d", "/dev/shm/mxl", "MXL domain")
+	videoFlow := flag.String("v", "", "Video flow UUID")
+	audioFlow := flag.String("a", "", "Audio flow UUID")
+	flag.Parse()
+	if *videoFlow == "" || *audioFlow == "" {
+		log.Fatal("need both -v <video-flow> and -a <audio-flow>")
+	}
+
+	inst, err := mxl.NewInstance(*domain, "")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer inst.Close()
+
+	vr, err := inst.NewReader(*videoFlow)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer vr.Close()
+
+	ar, err := inst.NewReader(*audioFlow)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer ar.Close()
+
+	vInfo, _ := vr.Info()
+	aInfo, _ := ar.Info()
+	vRate := vInfo.Config.Common.GrainRate
+	aRate := aInfo.Config.Common.GrainRate
+	aChans := aInfo.Config.Continuous.ChannelCount
+	fmt.Printf("video: %dx%d %d/%d | audio: %dch %d/%d\n",
+		vInfo.Config.Discrete.SliceSizes[0],
+		vInfo.Config.Discrete.GrainCount,
+		vRate.Num, vRate.Den,
+		aChans, aRate.Num, aRate.Den)
+
+	group, err := inst.NewSyncGroup()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer group.Close()
+	if err := group.AddReader(vr); err != nil {
+		log.Fatal(err)
+	}
+	if err := group.AddReader(ar); err != nil {
+		log.Fatal(err)
+	}
+
+	stop := make(chan os.Signal, 1)
+	signal.Notify(stop, os.Interrupt, syscall.SIGTERM)
+
+	idx := mxl.CurrentIndex(vRate)
+	audioBatch := uint64(aRate.Num / (100 * aRate.Den)) // ~10ms
+	if audioBatch == 0 {
+		audioBatch = 1
+	}
+
+	var ticks int
+	for {
+		select {
+		case <-stop:
+			fmt.Printf("\nstopped after %d ticks\n", ticks)
+			return
+		default:
+		}
+
+		ts := mxl.IndexToTimestamp(vRate, idx)
+		err := group.WaitForDataAt(ts, 500*time.Millisecond)
+		switch {
+		case err == nil:
+			// Read video grain
+			g, gerr := vr.GetGrain(idx, 50*time.Millisecond)
+			// Read audio samples at the same timestamp
+			aIdx := mxl.TimestampToIndex(aRate, ts)
+			_, aerr := ar.GetSamples(aIdx, int(audioBatch), 50*time.Millisecond)
+			if gerr != nil {
+				log.Printf("grain: %v", gerr)
+			} else if aerr != nil {
+				log.Printf("samples: %v", aerr)
+			} else {
+				fmt.Printf("tick idx=%d ts=%d grainSize=%d audioIdx=%d\n",
+					idx, ts, g.GrainSize, aIdx)
+				ticks++
+				if ticks >= 10 {
+					fmt.Println("done")
+					return
+				}
+			}
+			idx++
+		case errors.Is(err, mxl.ErrTimeout), errors.Is(err, mxl.ErrOutOfRangeEarly):
+			time.Sleep(5 * time.Millisecond)
+		case errors.Is(err, mxl.ErrOutOfRangeLate):
+			log.Printf("fell behind, resyncing")
+			idx = mxl.CurrentIndex(vRate)
+		default:
+			log.Fatalf("WaitForDataAt: %v", err)
+		}
+	}
+}
diff --git a/fixes.md b/fixes.md
new file mode 100644
index 0000000..858ea80
--- /dev/null
+++ b/fixes.md
@@ -0,0 +1,8 @@
+# List of bugs, that need to be fixed
+
+## Major
+## Minor
+- hotkeys on keyDown, especially toggle keys. Way to recreate: press F and hold
+
+## TODO:
+- q for quit