diff --git a/src/matebot/web/app.js b/src/matebot/web/app.js
index fe53f36..01cc9b4 100644
--- a/src/matebot/web/app.js
+++ b/src/matebot/web/app.js
@@ -92,7 +92,7 @@ function renderDetail(id, shot, compareId, compare) {
   if (shot.video) {
     const holder = document.createElement("div");
     holder.className = "chart-card video-card";
-    holder.innerHTML = `<video src="${esc(shot.video)}" playsinline muted preload="metadata"></video>
+    holder.innerHTML = `<video src="${esc(shot.video)}" playsinline muted preload="auto"></video>
       <button class="pbtn vunmute" title="Sound">🔇</button>`;
     charts.appendChild(holder);
     VIDEO = holder.querySelector("video");
@@ -171,6 +171,7 @@ function videoFollow(time, speed) {
   if (VIDEO.paused) {
     if (VIDEO.ended || VIDEO.currentTime >= (VIDEO.duration || Infinity)) return;
     VIDEO.play().catch(() => {});
+    return; // no drift correction until playback actually starts
   }
   const drift = VIDEO.currentTime - vt;
   if (Math.abs(drift) > 1) {
@@ -184,6 +185,15 @@ function videoFollow(time, speed) {
   }
 }
 
+// True while the playing video is waiting for data; the chart clock holds so
+// the curves never run ahead of a buffering video.
+function videoBuffering(time) {
+  if (!VIDEO || VIDEO.error || VIDEO.ended || VIDEO.paused) return false;
+  const vt = time + VIDEO_OFFSET;
+  if (vt < 0 || vt >= (VIDEO.duration || Infinity)) return false;
+  return VIDEO.readyState < 3 || VIDEO.seeking;
+}
+
 function combinedChart(parent, t, phases, S, overlay) {
   if (!t || t.length < 2 || typeof Chart === "undefined") return;
   Chart.register(window["chartjs-plugin-annotation"]);
@@ -396,7 +406,7 @@ function attachPlayer(card, t, xMax, S, overlay) {
 
   function tick(ts) {
     if (lastTs != null) {
-      playT += ((ts - lastTs) / 1000) * Number($("#speed").value);
+      if (!videoBuffering(playT)) playT += ((ts - lastTs) / 1000) * Number($("#speed").value);
       if (playT >= xMax) {
         playT = xMax;
         renderAt(playT, false);