diff --git a/app/static/js/services/soundfontPlayer.js b/app/static/js/services/soundfontPlayer.js
index 3404253..8faea4a 100644
--- a/app/static/js/services/soundfontPlayer.js
+++ b/app/static/js/services/soundfontPlayer.js
@@ -188,9 +188,22 @@
         // ════════════════════════════════════════════════
         selectInstrument: async function (channel, bank, program, sfId) {
             console.log("[SonicSF][DEBUG] PHASE3: selectInstrument ch=" + channel + " bank=" + bank + " prog=" + program + " sf=" + sfId + " _initialized=" + _initialized);
+            // Auto-init: create AudioContext + init SpessaSynth if not ready
             if (!_initialized || !_synthInstance) {
-                console.log("[SonicSF][DEBUG] PHASE3: engine not ready, returning");
-                return;
+                console.log("[SonicSF][DEBUG] PHASE3: engine not ready, triggering init...");
+                try {
+                    const ctx = new (window.AudioContext || window.webkitAudioContext)();
+                    if (ctx.state === 'suspended') await ctx.resume();
+                    await this.init(ctx);
+                } catch (e) {
+                    console.error("[SonicSF][DEBUG] PHASE3: auto-init failed:", e);
+                    return;
+                }
+                if (!_initialized || !_synthInstance) {
+                    console.warn("[SonicSF][DEBUG] PHASE3: engine still not ready after auto-init");
+                    return;
+                }
+                console.log("[SonicSF][DEBUG] PHASE3: auto-init complete");
             }
             // Phase 2 first: ensure SoundFont is loaded
             if (sfId) {