diff --git a/abogen/web/debug_tts_runner.py b/abogen/web/debug_tts_runner.py
index 9a54591..d8996ef 100644
--- a/abogen/web/debug_tts_runner.py
+++ b/abogen/web/debug_tts_runner.py
@@ -90,7 +90,29 @@ def run_debug_tts_wavs(
     if missing:
         raise RuntimeError(f"Debug EPUB missing expected codes: {', '.join(missing)}")
 
-    language = str(settings.get("language") or "en").strip() or "en"
+    language = str(settings.get("language") or "a").strip() or "a"
+    # Kokoro's KPipeline expects short language codes like "a" (American English),
+    # but older settings may store ISO-like values such as "en".
+    language_aliases = {
+        "en": "a",
+        "en-us": "a",
+        "en_us": "a",
+        "en-gb": "b",
+        "en_gb": "b",
+        "es": "e",
+        "es-es": "e",
+        "fr": "f",
+        "fr-fr": "f",
+        "hi": "h",
+        "it": "i",
+        "pt": "p",
+        "pt-br": "p",
+        "ja": "j",
+        "jp": "j",
+        "zh": "z",
+        "zh-cn": "z",
+    }
+    language = language_aliases.get(language.lower(), language)
     voice_spec = str(settings.get("default_voice") or "").strip()
     use_gpu = bool(settings.get("use_gpu", False))
     speed = float(settings.get("default_speed", 1.0) or 1.0)
diff --git a/abogen/web/routes/settings.py b/abogen/web/routes/settings.py
index b3340b2..30e166a 100644
--- a/abogen/web/routes/settings.py
+++ b/abogen/web/routes/settings.py
@@ -195,12 +195,38 @@ def run_debug_wavs() -> ResponseReturnValue:
         return redirect(url_for("settings.settings_page", _anchor="debug"))
 
     flash("Debug WAV generation completed.", "success")
-    return redirect(
-        url_for(
-            "settings.settings_page",
-            debug_run_id=str(manifest.get("run_id") or ""),
-            _anchor="debug",
-        )
+    return redirect(url_for("settings.debug_wavs_page", run_id=str(manifest.get("run_id") or "")))
+
+
+@settings_bp.get("/debug/<run_id>")
+def debug_wavs_page(run_id: str) -> ResponseReturnValue:
+    safe_run = (run_id or "").strip()
+    if not safe_run:
+        abort(404)
+
+    root = Path(current_app.config.get("OUTPUT_FOLDER") or get_user_output_path("web"))
+    run_dir = (root / "debug" / safe_run).resolve()
+    manifest_path = run_dir / "manifest.json"
+    if not manifest_path.exists():
+        abort(404)
+
+    try:
+        import json
+
+        manifest = json.loads(manifest_path.read_text(encoding="utf-8"))
+    except Exception:
+        abort(404)
+
+    artifacts = manifest.get("artifacts") or []
+    # Precompute download URLs for each artifact.
+    for item in artifacts:
+        filename = str(item.get("filename") or "")
+        item["url"] = url_for("settings.download_debug_wav", run_id=safe_run, filename=filename)
+
+    return render_template(
+        "debug_wavs.html",
+        run_id=safe_run,
+        artifacts=artifacts,
     )
 
 
diff --git a/abogen/web/templates/debug_wavs.html b/abogen/web/templates/debug_wavs.html
new file mode 100644
index 0000000..69b766b
--- /dev/null
+++ b/abogen/web/templates/debug_wavs.html
@@ -0,0 +1,61 @@
+{% extends "base.html" %}
+
+{% block title %}abogen · Debug WAVs{% endblock %}
+
+{% block content %}
+<section class="card">
+  <h1 class="card__title">Debug WAVs</h1>
+  <p class="tag">Run ID: <code>{{ run_id }}</code></p>
+
+  <div class="field field--stack">
+    <audio data-role="debug-audio" controls preload="none" style="width: 100%;"></audio>
+    <p class="hint">Click an ID to play its WAV. “Overall” is the concatenation of all samples.</p>
+  </div>
+
+  {% if artifacts %}
+  <div class="field field--wide">
+    <label>Samples</label>
+    <ul>
+      {% for item in artifacts %}
+      <li>
+        <button
+          type="button"
+          class="button button--ghost"
+          data-role="debug-play"
+          data-audio-src="{{ item.url }}"
+        >
+          {{ item.label }}
+        </button>
+        <a class="muted" href="{{ item.url }}" download>{{ item.filename }}</a>
+      </li>
+      {% endfor %}
+    </ul>
+  </div>
+  {% endif %}
+
+  <div class="field field--inline">
+    <a href="{{ url_for('settings.settings_page', _anchor='debug') }}" class="button button--ghost">Back to Settings</a>
+  </div>
+</section>
+
+<script>
+  (function () {
+    const audio = document.querySelector('[data-role="debug-audio"]');
+    const buttons = Array.from(document.querySelectorAll('[data-role="debug-play"]'));
+    if (!audio || !buttons.length) {
+      return;
+    }
+
+    buttons.forEach((button) => {
+      button.addEventListener('click', () => {
+        const src = button.dataset.audioSrc;
+        if (!src) return;
+        if (audio.src !== src) {
+          audio.src = src;
+        }
+        audio.play();
+      });
+    });
+  })();
+</script>
+{% endblock %}
diff --git a/tests/test_debug_tts_samples.py b/tests/test_debug_tts_samples.py
index aaa6c24..3b72b14 100644
--- a/tests/test_debug_tts_samples.py
+++ b/tests/test_debug_tts_samples.py
@@ -84,10 +84,10 @@ def test_settings_debug_route_writes_manifest(tmp_path, monkeypatch):
         resp = client.post("/settings/debug/run")
         assert resp.status_code in {302, 303}
         location = resp.headers.get("Location", "")
-        assert "debug_run_id=" in location
+        assert "/settings/debug/" in location
 
-        # Extract run id from query string.
-        run_id = location.split("debug_run_id=")[1].split("&")[0].split("#")[0]
+        # Extract run id from /settings/debug/<run_id>
+        run_id = location.rsplit("/settings/debug/", 1)[1].split("?", 1)[0].split("#", 1)[0]
         manifest_path = tmp_path / "debug" / run_id / "manifest.json"
         assert manifest_path.exists()