diff --git a/public/audio/ui-notify.mp3 b/public/audio/ui-notify.mp3
deleted file mode 100644
index 326d3fa533..0000000000
Binary files a/public/audio/ui-notify.mp3 and /dev/null differ
diff --git a/src/app/(dashboard)/dashboard/settings/components/ModelLockoutCard.tsx b/src/app/(dashboard)/dashboard/settings/components/ModelLockoutCard.tsx
index 3850268653..c44cdc85a0 100644
--- a/src/app/(dashboard)/dashboard/settings/components/ModelLockoutCard.tsx
+++ b/src/app/(dashboard)/dashboard/settings/components/ModelLockoutCard.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import { useCallback, useEffect, useRef, useState } from "react";
+import { useEffect, useRef, useState } from "react";
 import { Button, Card, Toggle } from "@/shared/components";
 import { useNotificationStore } from "@/store/notificationStore";
 import { useTranslations } from "next-intl";
@@ -23,6 +23,66 @@ const DEFAULTS: ModelLockoutSettings = {
   useExponentialBackoff: true,
 };
 
+type WebkitAudioWindow = Window & {
+  webkitAudioContext?: typeof AudioContext;
+};
+
+function scheduleNotifyChime(context: AudioContext): void {
+  const oscillator = context.createOscillator();
+  const gain = context.createGain();
+  const startsAt = context.currentTime;
+  const endsAt = startsAt + 0.1;
+
+  // A short, locally synthesized tone avoids shipping a third-party audio asset.
+  oscillator.type = "sine";
+  oscillator.frequency.setValueAtTime(880, startsAt);
+  gain.gain.setValueAtTime(0.0001, startsAt);
+  gain.gain.exponentialRampToValueAtTime(0.045, startsAt + 0.012);
+  gain.gain.exponentialRampToValueAtTime(0.0001, startsAt + 0.09);
+
+  oscillator.connect(gain);
+  gain.connect(context.destination);
+  oscillator.onended = () => {
+    oscillator.disconnect();
+    gain.disconnect();
+  };
+  oscillator.start(startsAt);
+  oscillator.stop(endsAt);
+}
+
+function playNotifyChime(contextRef: { current: AudioContext | null }): void {
+  try {
+    if (typeof window === "undefined") return;
+
+    const AudioContextConstructor =
+      window.AudioContext ?? (window as WebkitAudioWindow).webkitAudioContext;
+    if (!AudioContextConstructor) return;
+
+    if (!contextRef.current || contextRef.current.state === "closed") {
+      contextRef.current = new AudioContextConstructor();
+    }
+
+    const context = contextRef.current;
+    if (context.state !== "running") {
+      void context
+        .resume()
+        .then(() => {
+          try {
+            scheduleNotifyChime(context);
+          } catch {
+            // Sound is optional and must never block a settings change.
+          }
+        })
+        .catch(() => undefined);
+      return;
+    }
+
+    scheduleNotifyChime(context);
+  } catch {
+    // Sound is optional and must never block a settings change.
+  }
+}
+
 function NumberField({
   label,
   value,
@@ -71,6 +131,7 @@ export default function ModelLockoutCard() {
   const t = useTranslations("settings");
   const tc = useTranslations("common");
   const notify = useNotificationStore();
+  const notifyAudioContextRef = useRef<AudioContext | null>(null);
 
   const [data, setData] = useState<ModelLockoutSettings>(DEFAULTS);
   const [draft, setDraft] = useState<ModelLockoutSettings>(DEFAULTS);
@@ -78,6 +139,21 @@ export default function ModelLockoutCard() {
   const [loading, setLoading] = useState(true);
   const [saving, setSaving] = useState(false);
 
+  useEffect(
+    () => () => {
+      const context = notifyAudioContextRef.current;
+      notifyAudioContextRef.current = null;
+      if (context && context.state !== "closed") {
+        try {
+          void context.close().catch(() => undefined);
+        } catch {
+          // Sound cleanup is optional and must never block the page from unmounting.
+        }
+      }
+    },
+    []
+  );
+
   useEffect(() => {
     let mounted = true;
 
@@ -254,22 +330,6 @@ export default function ModelLockoutCard() {
     return `${ms}ms`;
   };
 
-  const notifyRef = useRef<HTMLAudioElement | null>(null);
-  const playNotify = useCallback(() => {
-    try {
-      if (notifyRef.current) {
-        notifyRef.current.pause();
-        notifyRef.current.currentTime = 0;
-      } else {
-        notifyRef.current = new Audio("/audio/ui-notify.mp3");
-        notifyRef.current.volume = 0.3;
-      }
-      void notifyRef.current.play();
-    } catch {
-      // Audio is optional.
-    }
-  }, []);
-
   if (loading) {
     return (
       <Card className="p-6">
@@ -314,7 +374,7 @@ export default function ModelLockoutCard() {
             checked={draft.enabled}
             onChange={(checked) => {
               setDraft((prev) => ({ ...prev, enabled: checked }));
-              playNotify();
+              playNotifyChime(notifyAudioContextRef);
             }}
             label={t("modelLockoutEnabled")}
             description={t("modelLockoutEnabledDescription")}
@@ -443,7 +503,7 @@ export default function ModelLockoutCard() {
                 ...prev,
                 useExponentialBackoff: checked,
               }));
-              playNotify();
+              playNotifyChime(notifyAudioContextRef);
             }}
             label={t("modelLockoutExponentialBackoff")}
             description={t("modelLockoutExponentialBackoffDescription")}
diff --git a/tests/unit/ui/model-lockout-notify-chime.test.tsx b/tests/unit/ui/model-lockout-notify-chime.test.tsx
new file mode 100644
index 0000000000..98cb9c8752
--- /dev/null
+++ b/tests/unit/ui/model-lockout-notify-chime.test.tsx
@@ -0,0 +1,252 @@
+// @vitest-environment jsdom
+import fs from "node:fs";
+import path from "node:path";
+import React, { act } from "react";
+import { createRoot, type Root } from "react-dom/client";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+const translate = (key: string) => key;
+const notifications = {
+  error: vi.fn(),
+  success: vi.fn(),
+};
+
+vi.mock("next-intl", () => ({
+  useTranslations: () => translate,
+}));
+
+vi.mock("@/store/notificationStore", () => ({
+  useNotificationStore: () => notifications,
+}));
+
+import ModelLockoutCard from "../../../src/app/(dashboard)/dashboard/settings/components/ModelLockoutCard";
+
+type OscillatorMock = {
+  connect: ReturnType<typeof vi.fn>;
+  disconnect: ReturnType<typeof vi.fn>;
+  frequency: { setValueAtTime: ReturnType<typeof vi.fn> };
+  onended: (() => void) | null;
+  start: ReturnType<typeof vi.fn>;
+  stop: ReturnType<typeof vi.fn>;
+  type: OscillatorType;
+};
+
+function createAudioContextMock(
+  options: { resumeRejects?: boolean; state?: AudioContextState } = {}
+) {
+  const contexts: AudioContextMock[] = [];
+  const oscillators: OscillatorMock[] = [];
+  const gains: Array<{
+    connect: ReturnType<typeof vi.fn>;
+    disconnect: ReturnType<typeof vi.fn>;
+    gain: {
+      cancelScheduledValues: ReturnType<typeof vi.fn>;
+      exponentialRampToValueAtTime: ReturnType<typeof vi.fn>;
+      setValueAtTime: ReturnType<typeof vi.fn>;
+    };
+  }> = [];
+
+  class AudioContextMock {
+    close = vi.fn().mockResolvedValue(undefined);
+    currentTime = 1;
+    destination = {};
+    state: AudioContextState = options.state ?? "running";
+    resume = options.resumeRejects
+      ? vi.fn().mockRejectedValue(new Error("audio resume denied"))
+      : vi.fn().mockResolvedValue(undefined);
+
+    constructor() {
+      contexts.push(this);
+    }
+
+    createOscillator() {
+      const oscillator: OscillatorMock = {
+        connect: vi.fn(),
+        disconnect: vi.fn(),
+        frequency: { setValueAtTime: vi.fn() },
+        onended: null,
+        start: vi.fn(),
+        stop: vi.fn(),
+        type: "sine",
+      };
+      oscillators.push(oscillator);
+      return oscillator;
+    }
+
+    createGain() {
+      const gain = {
+        connect: vi.fn(),
+        disconnect: vi.fn(),
+        gain: {
+          cancelScheduledValues: vi.fn(),
+          exponentialRampToValueAtTime: vi.fn(),
+          setValueAtTime: vi.fn(),
+        },
+      };
+      gains.push(gain);
+      return gain;
+    }
+  }
+
+  return { AudioContextMock, contexts, gains, oscillators };
+}
+
+const roots: Array<{ container: HTMLDivElement; root: Root }> = [];
+
+async function renderCard(): Promise<{ container: HTMLDivElement; root: Root }> {
+  const container = document.createElement("div");
+  document.body.appendChild(container);
+  const root = createRoot(container);
+  roots.push({ container, root });
+
+  await act(async () => {
+    root.render(<ModelLockoutCard />);
+    await Promise.resolve();
+    await Promise.resolve();
+  });
+
+  return { container, root };
+}
+
+function disposeCard(rendered: { container: HTMLDivElement; root: Root }): void {
+  act(() => rendered.root.unmount());
+  rendered.container.remove();
+  const index = roots.findIndex(({ root }) => root === rendered.root);
+  if (index >= 0) roots.splice(index, 1);
+}
+
+describe("Model lockout optional notification sound", () => {
+  beforeEach(() => {
+    (
+      globalThis as typeof globalThis & { IS_REACT_ACT_ENVIRONMENT?: boolean }
+    ).IS_REACT_ACT_ENVIRONMENT = true;
+    vi.stubGlobal(
+      "fetch",
+      vi.fn().mockResolvedValue(
+        new Response(
+          JSON.stringify({
+            modelLockout: {
+              enabled: false,
+              errorCodes: [403, 404, 429, 502, 503, 504],
+              baseCooldownMs: 120_000,
+              maxCooldownMs: 1_800_000,
+              maxBackoffSteps: 10,
+              useExponentialBackoff: true,
+            },
+          }),
+          { status: 200 }
+        )
+      )
+    );
+  });
+
+  afterEach(() => {
+    for (const { container, root } of roots) {
+      act(() => root.unmount());
+      container.remove();
+    }
+    roots.length = 0;
+    vi.unstubAllGlobals();
+    vi.clearAllMocks();
+  });
+
+  it("does not ship or reference the unprovenanced MP3", () => {
+    const legacyAssetName = "ui-notify.mp3";
+    const legacyAssetUrl = ["/audio", legacyAssetName].join("/");
+    const assetPath = path.join(process.cwd(), "public/audio", legacyAssetName);
+    const componentPath = path.join(
+      process.cwd(),
+      "src/app/(dashboard)/dashboard/settings/components/ModelLockoutCard.tsx"
+    );
+
+    expect(fs.existsSync(assetPath)).toBe(false);
+    expect(fs.readFileSync(componentPath, "utf8")).not.toContain(legacyAssetUrl);
+  });
+
+  it("plays generated feedback for both model-lockout toggles", async () => {
+    const { AudioContextMock, oscillators } = createAudioContextMock();
+    vi.stubGlobal("AudioContext", AudioContextMock);
+    const legacyAudio = vi.fn(() => ({
+      currentTime: 0,
+      pause: vi.fn(),
+      play: vi.fn(),
+      volume: 1,
+    }));
+    vi.stubGlobal("Audio", legacyAudio);
+
+    const { container } = await renderCard();
+    const toggles = [...container.querySelectorAll<HTMLButtonElement>('button[role="switch"]')];
+    expect(toggles).toHaveLength(2);
+
+    act(() => toggles[0]?.click());
+    act(() => toggles[1]?.click());
+
+    expect(oscillators).toHaveLength(2);
+    expect(oscillators.every((oscillator) => oscillator.start.mock.calls.length === 1)).toBe(true);
+    expect(oscillators.every((oscillator) => oscillator.stop.mock.calls.length === 1)).toBe(true);
+    expect(legacyAudio).not.toHaveBeenCalled();
+  });
+
+  it("starts the optional chime after a suspended context resumes", async () => {
+    const { AudioContextMock, contexts, oscillators } = createAudioContextMock({
+      state: "suspended",
+    });
+    vi.stubGlobal("AudioContext", AudioContextMock);
+
+    const { container } = await renderCard();
+    const toggle = container.querySelector<HTMLButtonElement>('button[role="switch"]');
+    await act(async () => {
+      toggle?.click();
+      await Promise.resolve();
+    });
+
+    expect(contexts[0]?.resume).toHaveBeenCalledOnce();
+    expect(oscillators).toHaveLength(1);
+  });
+
+  it("keeps both toggles working when Web Audio is unavailable", async () => {
+    vi.stubGlobal("AudioContext", undefined);
+
+    const { container } = await renderCard();
+    const toggles = [...container.querySelectorAll<HTMLButtonElement>('button[role="switch"]')];
+    act(() => toggles[0]?.click());
+    act(() => toggles[1]?.click());
+
+    expect(toggles[0]?.getAttribute("aria-checked")).toBe("true");
+    expect(toggles[1]?.getAttribute("aria-checked")).toBe("false");
+  });
+
+  it("keeps the toggle working when a suspended context cannot resume", async () => {
+    const { AudioContextMock, contexts, oscillators } = createAudioContextMock({
+      resumeRejects: true,
+      state: "suspended",
+    });
+    vi.stubGlobal("AudioContext", AudioContextMock);
+
+    const { container } = await renderCard();
+    const toggle = container.querySelector<HTMLButtonElement>('button[role="switch"]');
+    await act(async () => {
+      toggle?.click();
+      await Promise.resolve();
+      await Promise.resolve();
+    });
+
+    expect(toggle?.getAttribute("aria-checked")).toBe("true");
+    expect(contexts[0]?.resume).toHaveBeenCalledOnce();
+    expect(oscillators).toHaveLength(0);
+  });
+
+  it("releases its audio context when the settings card unmounts", async () => {
+    const { AudioContextMock, contexts } = createAudioContextMock();
+    vi.stubGlobal("AudioContext", AudioContextMock);
+
+    const rendered = await renderCard();
+    const toggle = rendered.container.querySelector<HTMLButtonElement>('button[role="switch"]');
+    act(() => toggle?.click());
+    expect(contexts).toHaveLength(1);
+
+    disposeCard(rendered);
+
+    expect(contexts[0]?.close).toHaveBeenCalledOnce();
+  });
+});