diff --git a/src/lib/client/audiobooks/pipeline.ts b/src/lib/client/audiobooks/pipeline.ts
index 295cef4..56c9def 100644
--- a/src/lib/client/audiobooks/pipeline.ts
+++ b/src/lib/client/audiobooks/pipeline.ts
@@ -86,6 +86,12 @@ function isAbortLikeError(error: unknown): boolean {
   return error instanceof Error && (error.name === 'AbortError' || error.message.includes('cancelled'));
 }
 
+function createAudiobookAbortError(): Error {
+  const error = new Error('Audiobook generation cancelled');
+  error.name = 'AbortError';
+  return error;
+}
+
 export async function runAudiobookGeneration({
   adapter,
   apiKey,
@@ -120,7 +126,9 @@ export async function runAudiobookGeneration({
       const existingData = await getAudiobookStatus(bookId);
       if (existingData.chapters && existingData.chapters.length > 0) {
         for (const chapter of existingData.chapters) {
-          existingIndices.add(chapter.index);
+          if (chapter.status === 'completed') {
+            existingIndices.add(chapter.index);
+          }
         }
       }
     } catch (error) {
@@ -130,10 +138,7 @@ export async function runAudiobookGeneration({
 
   for (const chapter of chapters) {
     if (signal?.aborted) {
-      if (bookId) {
-        return bookId;
-      }
-      throw new Error('Audiobook generation cancelled');
+      throw createAudiobookAbortError();
     }
 
     const trimmedText = chapter.text.trim();
@@ -167,10 +172,7 @@ export async function runAudiobookGeneration({
       );
 
       if (signal?.aborted) {
-        if (bookId) {
-          return bookId;
-        }
-        throw new Error('Audiobook generation cancelled');
+        throw createAudiobookAbortError();
       }
 
       if (!bookId) {
@@ -186,10 +188,7 @@ export async function runAudiobookGeneration({
       onProgress((processedLength / totalLength) * 100);
     } catch (error) {
       if (isAbortLikeError(error)) {
-        if (bookId) {
-          return bookId;
-        }
-        throw new Error('Audiobook generation cancelled');
+        throw createAudiobookAbortError();
       }
 
       console.error('Error processing chapter:', error);
@@ -200,6 +199,8 @@ export async function runAudiobookGeneration({
         bookId,
         format: effectiveFormat,
       });
+      processedLength += trimmedText.length;
+      onProgress((processedLength / totalLength) * 100);
     }
   }
 
diff --git a/src/lib/client/config/preferences.ts b/src/lib/client/config/preferences.ts
index 261a000..5091078 100644
--- a/src/lib/client/config/preferences.ts
+++ b/src/lib/client/config/preferences.ts
@@ -8,6 +8,9 @@ function isObjectLike(value: unknown): value is Record<string, unknown> {
 function deepEqual(left: unknown, right: unknown): boolean {
   if (left === right) return true;
 
+  if (Array.isArray(left) !== Array.isArray(right)) return false;
+  if (isObjectLike(left) !== isObjectLike(right)) return false;
+
   if (Array.isArray(left) && Array.isArray(right)) {
     if (left.length !== right.length) return false;
     for (let i = 0; i < left.length; i += 1) {
diff --git a/src/lib/shared/tts-provider-catalog.ts b/src/lib/shared/tts-provider-catalog.ts
index 4713b34..fd26aff 100644
--- a/src/lib/shared/tts-provider-catalog.ts
+++ b/src/lib/shared/tts-provider-catalog.ts
@@ -205,15 +205,23 @@ async function fetchDeepinfraVoices(apiKey: string): Promise<string[]> {
 }
 
 async function fetchCustomOpenAiVoices(baseUrl: string, apiKey: string): Promise<string[] | null> {
+  const controller = new AbortController();
+  const timeoutId = setTimeout(() => {
+    controller.abort();
+  }, 10_000);
+
   try {
     const normalizedBaseUrl = baseUrl.replace(/\/+$/, '');
     const response = await fetch(`${normalizedBaseUrl}/audio/voices`, {
+      signal: controller.signal,
       headers: {
         Authorization: `Bearer ${apiKey}`,
         'Content-Type': 'application/json',
       },
     });
 
+    clearTimeout(timeoutId);
+
     if (!response.ok) {
       return null;
     }
@@ -221,6 +229,7 @@ async function fetchCustomOpenAiVoices(baseUrl: string, apiKey: string): Promise
     const data = await response.json();
     return Array.isArray(data.voices) ? data.voices : null;
   } catch {
+    clearTimeout(timeoutId);
     console.log('Custom endpoint does not support voices, using defaults');
     return null;
   }