diff --git a/assets/css/creator.css b/assets/css/creator.css
index 18185720..abeaa6cf 100755
--- a/assets/css/creator.css
+++ b/assets/css/creator.css
@@ -318,11 +318,21 @@ body.sidebar-hidden .sample-browser { width: 0; min-width: 0; border-right: none
 }
 /* CORREÇÃO CSS: Adicionado para garantir layout correto */
 .audio-tracks-wrapper {
-    flex: 1;
-    display: flex;
-    flex-direction: column;
-    position: relative;
-    overflow: hidden;
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  position: relative;
+  overflow: hidden;
+  position: relative;
+  overflow-x: auto;   /* barra horizontal */
+  overflow-y: auto;   /* se quiser rolar vertical com várias tracks */
+}
+
+/* Importantíssimo: esses caras precisam poder ficar mais largos que a tela */
+#audio-timeline-ruler,
+#audio-track-container{
+  position: relative;
+  min-width: 100%;    /* no mínimo ocupa a viewport */
 }
 
 #audio-track-container { flex-grow: 1; overflow: auto; }
diff --git a/assets/js/creations/audio/audio_ui.js b/assets/js/creations/audio/audio_ui.js
index 3b50375b..e6d4808c 100755
--- a/assets/js/creations/audio/audio_ui.js
+++ b/assets/js/creations/audio/audio_ui.js
@@ -57,19 +57,47 @@ export function renderAudioEditor() {
 
   const pixelsPerSecond = getPixelsPerSecond();
 
-  let maxTime = appState.global.loopEndTime;
-  appState.audio.clips.forEach((clip) => {
+  let maxTime = appState.global.loopEndTime || 0;
+
+  // áudio (segundos)
+  (appState.audio.clips || []).forEach((clip) => {
     const endTime =
       (clip.startTimeInSeconds || 0) + (clip.durationInSeconds || 0);
     if (endTime > maxTime) maxTime = endTime;
   });
 
-  const containerWidth = existingTrackContainer.offsetWidth;
+  // basslines (ticks -> steps -> segundos)
+  const TICKS_PER_STEP = 12; // você já usa 12 na renderização do bassline
+  const secondsPerStep = getSecondsPerStep();
+
+  if (appState.pattern?.tracks) {
+    appState.pattern.tracks.forEach((t) => {
+      if (t.type !== "bassline" || !Array.isArray(t.playlist_clips)) return;
+
+      t.playlist_clips.forEach((c) => {
+        const endTicks = (c.pos || 0) + (c.len || 0);
+        const endSteps = endTicks / TICKS_PER_STEP;
+        const endTimeSec = endSteps * secondsPerStep;
+        if (endTimeSec > maxTime) maxTime = endTimeSec;
+      });
+    });
+  }
+
+  const containerWidth =
+  tracksParent.clientWidth || existingTrackContainer.offsetWidth;
+
   const contentWidth = maxTime * pixelsPerSecond;
-  const totalWidth = Math.max(contentWidth, containerWidth, 2000);
+
+  // não encolhe se já tiver sido expandido antes
+  const previousWidth = appState.audio.timelineWidthPx || 0;
+
+  const totalWidth = Math.max(contentWidth, containerWidth, previousWidth, 2000);
+
+  appState.audio.timelineWidthPx = totalWidth;
 
   ruler.style.width = `${totalWidth}px`;
 
+
   const zoomFactor = ZOOM_LEVELS[appState.global.zoomLevelIndex];
   const beatsPerBar = getBeatsPerBar();
   const stepWidthPx = PIXELS_PER_STEP * zoomFactor;
@@ -461,14 +489,61 @@ export function renderAudioEditor() {
   });
 
   // Sync Scroll
+  function appendRulerMarkers(rulerEl, oldWidth, newWidth, barWidthPx) {
+    if (!rulerEl || barWidthPx <= 0) return;
+
+    const loopEl = rulerEl.querySelector("#loop-region");
+    const startBar = Math.floor(oldWidth / barWidthPx) + 1;
+    const endBar = Math.ceil(newWidth / barWidthPx);
+
+    for (let i = startBar; i <= endBar; i++) {
+      const marker = document.createElement("div");
+      marker.className = "ruler-marker";
+      marker.textContent = i;
+      marker.style.left = `${(i - 1) * barWidthPx}px`;
+      // mantém loop por cima/ordem estável
+      rulerEl.insertBefore(marker, loopEl || null);
+    }
+  }
+
+  function applyTimelineWidth(widthPx) {
+    appState.audio.timelineWidthPx = widthPx;
+
+    const r = tracksParent.querySelector(".timeline-ruler");
+    if (r) r.style.width = `${widthPx}px`;
+
+    tracksParent
+      .querySelectorAll(".spectrogram-view-grid")
+      .forEach((g) => (g.style.width = `${widthPx}px`));
+  }
+
   newTrackContainer.addEventListener("scroll", () => {
     const scrollPos = newTrackContainer.scrollLeft;
-    const mainRuler = document.querySelector(".timeline-ruler");
+
+    // sync ruler
+    const mainRuler = tracksParent.querySelector(".timeline-ruler");
     if (mainRuler && mainRuler.scrollLeft !== scrollPos) {
       mainRuler.scrollLeft = scrollPos;
     }
+
+    // expansão "infinita"
+    const threshold = 300;
+    const rightEdge = scrollPos + newTrackContainer.clientWidth;
+    const currentWidth = appState.audio.timelineWidthPx || totalWidth;
+
+    if (rightEdge > currentWidth - threshold) {
+      const newWidth = Math.ceil(currentWidth * 1.5);
+
+      // aplica widths
+      applyTimelineWidth(newWidth);
+
+      // adiciona mais marcadores na régua (sem re-render geral)
+      const rulerEl = tracksParent.querySelector(".timeline-ruler");
+      appendRulerMarkers(rulerEl, currentWidth, newWidth, barWidthPx);
+    }
   });
 
+
   // Event Listener Principal (mousedown)
   newTrackContainer.addEventListener("mousedown", (e) => {
     document.getElementById("timeline-context-menu").style.display = "none";