diff --git a/frontend/src/components/OnboardingWizard/PersonalizationStep/components/TestPersonaModal.tsx b/frontend/src/components/OnboardingWizard/PersonalizationStep/components/TestPersonaModal.tsx
index e9d65f0b..57d932e5 100644
--- a/frontend/src/components/OnboardingWizard/PersonalizationStep/components/TestPersonaModal.tsx
+++ b/frontend/src/components/OnboardingWizard/PersonalizationStep/components/TestPersonaModal.tsx
@@ -10,7 +10,7 @@ import {
 import { createAvatarVideoAsync } from '../../../../api/videoStudioApi';
 import { useVideoGenerationPolling } from '../../../../hooks/usePolling';
 import { fetchMediaBlobUrl } from '../../../../utils/fetchMediaBlobUrl';
-import { getAuthTokenGetter } from '../../../../api/client';
+import { getAuthTokenGetter, getApiUrl } from '../../../../api/client';
 import { VideoCameraFront, SkipNext, PlayArrow, InfoOutlined, Close as CloseIcon, HelpOutline, Refresh, RestartAlt, Undo } from '@mui/icons-material';
 import { VideoGenerationLoader } from '../../../shared/VideoGenerationLoader';
 import { OperationButton } from '../../../shared/OperationButton';
@@ -49,8 +49,9 @@ export const TestPersonaModal: React.FC<TestPersonaModalProps> = ({
         if (tokenGetter) {
           const token = await tokenGetter();
           if (token && !cancelled) {
-            const sep = voiceUrl.includes('?') ? '&' : '?';
-            setAuthenticatedVoiceUrl(`${voiceUrl}${sep}token=${encodeURIComponent(token)}`);
+            const absoluteUrl = voiceUrl.startsWith('/') ? `${getApiUrl()}${voiceUrl}` : voiceUrl;
+            const sep = absoluteUrl.includes('?') ? '&' : '?';
+            setAuthenticatedVoiceUrl(`${absoluteUrl}${sep}token=${encodeURIComponent(token)}`);
             return;
           }
         }
diff --git a/frontend/src/components/OnboardingWizard/PersonalizationStep/components/VoiceAvatarPlaceholder.tsx b/frontend/src/components/OnboardingWizard/PersonalizationStep/components/VoiceAvatarPlaceholder.tsx
index 662d253f..74bed5cb 100644
--- a/frontend/src/components/OnboardingWizard/PersonalizationStep/components/VoiceAvatarPlaceholder.tsx
+++ b/frontend/src/components/OnboardingWizard/PersonalizationStep/components/VoiceAvatarPlaceholder.tsx
@@ -3,7 +3,7 @@ import { Box, Typography, Paper, Stack, Button, Alert, TextField, CircularProgre
 import { keyframes } from '@mui/system';
 import { Mic, GraphicEq, Timer, CloudUpload, Stop, PlayArrow, InfoOutlined, TextFields, HelpOutline, AutoAwesome, Campaign, MicNone, Podcasts, RestartAlt, Undo, Headphones, Article, VideoLibrary, TrendingUp, CheckCircle, RecordVoiceOver, Settings } from '@mui/icons-material';
 import { createVoiceClone, createVoiceDesign, getLatestVoiceClone, setBrandVoice } from '../../../../api/brandAssets';
-import { getAuthTokenGetter } from '../../../../api/client';
+import { getAuthTokenGetter, getApiUrl } from '../../../../api/client';
 import { OperationButton } from '../../../shared/OperationButton';
 
 const pulse = keyframes`
@@ -114,8 +114,9 @@ export const VoiceAvatarPlaceholder: React.FC<{ domainName?: string; onVoiceSet?
           const token = await tokenGetter();
           console.log('[VoiceClone] Got token:', token ? 'yes' : 'no');
           if (token && !cancelled) {
-            const sep = resultAudioUrl.includes('?') ? '&' : '?';
-            const authUrl = `${resultAudioUrl}${sep}token=${encodeURIComponent(token)}`;
+            const absoluteUrl = resultAudioUrl.startsWith('/') ? `${getApiUrl()}${resultAudioUrl}` : resultAudioUrl;
+            const sep = absoluteUrl.includes('?') ? '&' : '?';
+            const authUrl = `${absoluteUrl}${sep}token=${encodeURIComponent(token)}`;
             console.log('[VoiceClone] Setting authenticatedAudioUrl:', authUrl);
             setAuthenticatedAudioUrl(authUrl);
             return;
diff --git a/frontend/src/components/shared/VoiceSelector.tsx b/frontend/src/components/shared/VoiceSelector.tsx
index 03332b23..4c4d8af6 100644
--- a/frontend/src/components/shared/VoiceSelector.tsx
+++ b/frontend/src/components/shared/VoiceSelector.tsx
@@ -43,7 +43,7 @@ import {
   Category,
 } from "@mui/icons-material";
 import { getLatestVoiceClone, VoiceCloneResponse } from "../../api/brandAssets";
-import { getAuthTokenGetter } from "../../api/client";
+import { getAuthTokenGetter, getApiUrl } from "../../api/client";
 import { VoiceAvatarPlaceholder } from "../OnboardingWizard/PersonalizationStep/components/VoiceAvatarPlaceholder";
 
 export type VoiceOption = {
@@ -250,6 +250,10 @@ export const VoiceSelector: React.FC<VoiceSelectorProps> = ({
 
     // Append auth token for endpoints that require it (e.g. /api/assets/)
     let previewUrl = voice.previewUrl;
+    // Convert relative URLs to absolute (pointing to backend, not Vercel)
+    if (previewUrl.startsWith('/')) {
+      previewUrl = `${getApiUrl()}${previewUrl}`;
+    }
     try {
       const tokenGetter = getAuthTokenGetter();
       if (tokenGetter) {