diff --git a/tests/e2e/online_serving/test_qwen3_omni_expansion.py b/tests/e2e/online_serving/test_qwen3_omni_expansion.py
index 1637627695e..3065439084a 100644
--- a/tests/e2e/online_serving/test_qwen3_omni_expansion.py
+++ b/tests/e2e/online_serving/test_qwen3_omni_expansion.py
@@ -29,6 +29,16 @@
 IMAGE_KEY = ["square", "quadrate", "rectangle"]
 VIDEO_KEY = ["sphere", "globe", "circle", "round", "ball"]
 
+# Heavier synthetic inputs than the default expansion cases (longer timeline / more pixels).
+# Long video: 120s @ 30fps => 3600 frames (generate_synthetic_video in tests/conftest.py).
+# Use 224² spatial size to bound RAM (~W*H*num_frames*3) vs. 288² at this frame count.
+LONG_VIDEO_WIDTH = 224
+LONG_VIDEO_HEIGHT = 224
+LONG_VIDEO_FRAMES = 3600
+LARGE_IMAGE_WIDTH = 1920
+LARGE_IMAGE_HEIGHT = 1080
+LONG_AUDIO_DURATION_SEC = 120
+
 
 def get_chunk_config(default_path):
     path = modify_stage_config(
@@ -37,7 +47,8 @@ def get_chunk_config(default_path):
             "async_chunk": True,
             "stage_args": {
                 0: {
-                    "engine_args.custom_process_next_stage_input_func": "vllm_omni.model_executor.stage_input_processors.qwen3_omni.thinker2talker_async_chunk"
+                    "engine_args.custom_process_next_stage_input_func": "vllm_omni.model_executor.stage_input_processors.qwen3_omni.thinker2talker_async_chunk",
+                    "default_sampling_params.max_tokens": 2048,
                 },
                 1: {
                     "engine_args.custom_process_next_stage_input_func": "vllm_omni.model_executor.stage_input_processors.qwen3_omni.talker2code2wav_async_chunk"
@@ -167,88 +178,17 @@ def test_text_to_text_audio_001(omni_server, openai_client) -> None:
 @pytest.mark.omni
 @hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
 @pytest.mark.parametrize("omni_server", test_params, indirect=True)
-def test_image_to_text_001(omni_server, openai_client) -> None:
-    """
-    Input Modal: image
-    Output Modal: text
-    Input Setting: stream=True
-    Datasets: single request
-    """
-    image_data_url = f"data:image/jpeg;base64,{generate_synthetic_image(224, 224)['base64']}"
-    messages = dummy_messages_from_mix_data(image_data_url=image_data_url)
-
-    request_config = {
-        "model": omni_server.model,
-        "messages": messages,
-        "modalities": ["text"],
-        "stream": True,
-        "key_words": {"image": IMAGE_KEY},
-    }
-
-    openai_client.send_omni_request(request_config)
-
-
-@pytest.mark.advanced_model
-@pytest.mark.omni
-@hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
-@pytest.mark.parametrize("omni_server", test_params, indirect=True)
-def test_image_to_audio_001(omni_server, openai_client) -> None:
-    """
-    Input Modal: image
-    Output Modal: audio
-    Input Setting: stream=False
-    Datasets: single request
-    """
-    image_data_url = f"data:image/jpeg;base64,{generate_synthetic_image(224, 224)['base64']}"
-    messages = dummy_messages_from_mix_data(image_data_url=image_data_url)
-
-    request_config = {
-        "model": omni_server.model,
-        "messages": messages,
-        "modalities": ["audio"],
-        "key_words": {"image": IMAGE_KEY},
-    }
-
-    openai_client.send_omni_request(request_config)
-
-
-@pytest.mark.advanced_model
-@pytest.mark.omni
-@hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
-@pytest.mark.parametrize("omni_server", test_params, indirect=True)
-def test_image_to_text_audio_001(omni_server, openai_client) -> None:
-    """
-    Input Modal: image
-    Output Modal: text, audio
-    Input Setting: stream=False
-    Datasets: few requests
-    """
-    image_data_url = f"data:image/jpeg;base64,{generate_synthetic_image(1280, 720)['base64']}"
-
-    messages = dummy_messages_from_mix_data(image_data_url=image_data_url)
-
-    request_config = {
-        "model": omni_server.model,
-        "messages": messages,
-        "key_words": {"image": IMAGE_KEY},
-    }
-
-    openai_client.send_omni_request(request_config, request_num=get_max_batch_size())
-
-
-@pytest.mark.advanced_model
-@pytest.mark.omni
-@hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
-@pytest.mark.parametrize("omni_server", test_params, indirect=True)
-def test_video_to_text_001(omni_server, openai_client) -> None:
+def test_text_video_to_text_001(omni_server, openai_client) -> None:
     """
-    Input Modal: video
+    Input Modal: long synthetic video (120s @ 30fps, LONG_VIDEO_FRAMES frames)
     Output Modal: text
     Input Setting: stream=False
     Datasets: single request
     """
-    video_data_url = f"data:video/mp4;base64,{generate_synthetic_video(224, 224, 300)['base64']}"
-    messages = dummy_messages_from_mix_data(video_data_url=video_data_url)
+    video_data_url = f"data:video/mp4;base64,{generate_synthetic_video(LONG_VIDEO_WIDTH, LONG_VIDEO_HEIGHT, LONG_VIDEO_FRAMES)['base64']}"
+    messages = dummy_messages_from_mix_data(
+        video_data_url=video_data_url, system_prompt=get_system_prompt(), content_text=get_prompt("text_video")
+    )
 
     request_config = {
         "model": omni_server.model,
@@ -257,28 +197,29 @@ def test_video_to_text_001(omni_server, openai_client) -> None:
         "key_words": {"video": VIDEO_KEY},
     }
 
-    openai_client.send_omni_request(request_config)
+    openai_client.send_omni_request(request_config, request_num=get_max_batch_size())
 
 
 @pytest.mark.advanced_model
 @pytest.mark.omni
 @hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
-@pytest.mark.parametrize("omni_server", test_params, indirect=True)
-def test_video_to_audio_001(omni_server, openai_client) -> None:
+@pytest.mark.parametrize("omni_server", test_params + test_token_params, indirect=True)
+def test_text_audio_to_text_audio_001(omni_server, openai_client) -> None:
     """
-    Input Modal: video
-    Output Modal: audio
+    Input Modal: text, audio
+    Output Modal: text, audio
     Input Setting: stream=False
     Datasets: single request
     """
-    video_data_url = f"data:video/mp4;base64,{generate_synthetic_video(224, 224, 300)['base64']}"
-    messages = dummy_messages_from_mix_data(video_data_url=video_data_url)
+    audio_data_url = f"data:audio/wav;base64,{generate_synthetic_audio(5, 1)['base64']}"
+    messages = dummy_messages_from_mix_data(
+        audio_data_url=audio_data_url, system_prompt=get_system_prompt(), content_text=get_prompt("text_audio")
+    )
 
     request_config = {
         "model": omni_server.model,
         "messages": messages,
-        "modalities": ["audio"],
-        "key_words": {"video": VIDEO_KEY},
+        "key_words": {"audio": AUDIO_KEY},
     }
 
     openai_client.send_omni_request(request_config)
@@ -287,22 +228,25 @@ def test_video_to_audio_001(omni_server, openai_client) -> None:
 @pytest.mark.advanced_model
 @pytest.mark.omni
 @hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
-@pytest.mark.parametrize("omni_server", test_params, indirect=True)
-def test_video_to_text_audio_001(omni_server, openai_client) -> None:
+@pytest.mark.parametrize("omni_server", test_params + test_token_params, indirect=True)
+def test_text_audio_to_text_audio_002(omni_server, openai_client) -> None:
     """
-    Input Modal: video
+    Input Modal: text, long-duration audio (~LONG_AUDIO_DURATION_SEC s WAV)
     Output Modal: text, audio
     Input Setting: stream=False
-    Datasets: few requests
+    Datasets: single request
     """
-    video_data_url = f"data:video/mp4;base64,{generate_synthetic_video(224, 224, 300)['base64']}"
-
-    messages = dummy_messages_from_mix_data(video_data_url=video_data_url)
+    audio_data_url = f"data:audio/wav;base64,{generate_synthetic_audio(LONG_AUDIO_DURATION_SEC, 1)['base64']}"
+    messages = dummy_messages_from_mix_data(
+        audio_data_url=audio_data_url,
+        system_prompt=get_system_prompt(),
+        content_text=get_prompt("text_audio"),
+    )
 
     request_config = {
         "model": omni_server.model,
         "messages": messages,
-        "key_words": {"video": VIDEO_KEY},
+        "key_words": {"audio": AUDIO_KEY},
     }
 
     openai_client.send_omni_request(request_config, request_num=get_max_batch_size())
@@ -312,22 +256,23 @@ def test_video_to_text_audio_001(omni_server, openai_client) -> None:
 @pytest.mark.omni
 @hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
 @pytest.mark.parametrize("omni_server", test_params + test_token_params, indirect=True)
-def test_text_audio_to_text_audio_001(omni_server, openai_client) -> None:
+def test_text_image_to_text_audio_001(omni_server, openai_client) -> None:
     """
-    Input Modal: text, audio
+    Input Modal: text, image
     Output Modal: text, audio
     Input Setting: stream=False
     Datasets: single request
     """
-    audio_data_url = f"data:audio/wav;base64,{generate_synthetic_audio(5, 1)['base64']}"
+    image_data_url = f"data:image/jpeg;base64,{generate_synthetic_image(224, 224)['base64']}"
+
     messages = dummy_messages_from_mix_data(
-        audio_data_url=audio_data_url, system_prompt=get_system_prompt(), content_text=get_prompt("text_audio")
+        image_data_url=image_data_url, system_prompt=get_system_prompt(), content_text=get_prompt("text_image")
     )
 
     request_config = {
         "model": omni_server.model,
         "messages": messages,
-        "key_words": {"audio": AUDIO_KEY},
+        "key_words": {"image": IMAGE_KEY},
     }
 
     openai_client.send_omni_request(request_config)
@@ -337,17 +282,21 @@ def test_text_audio_to_text_audio_001(omni_server, openai_client) -> None:
 @pytest.mark.omni
 @hardware_test(res={"cuda": "H100", "rocm": "MI325"}, num_cards=2)
 @pytest.mark.parametrize("omni_server", test_params + test_token_params, indirect=True)
-def test_text_image_to_text_audio_001(omni_server, openai_client) -> None:
+def test_large_image_to_text_audio_001(omni_server, openai_client) -> None:
     """
-    Input Modal: text, image
+    Input Modal: text, high-resolution image (1080p-class JPEG)
     Output Modal: text, audio
     Input Setting: stream=False
     Datasets: single request
     """
-    image_data_url = f"data:image/jpeg;base64,{generate_synthetic_image(224, 224)['base64']}"
+    image_data_url = (
+        f"data:image/jpeg;base64,{generate_synthetic_image(LARGE_IMAGE_WIDTH, LARGE_IMAGE_HEIGHT)['base64']}"
+    )
 
     messages = dummy_messages_from_mix_data(
-        image_data_url=image_data_url, system_prompt=get_system_prompt(), content_text=get_prompt("text_image")
+        image_data_url=image_data_url,
+        system_prompt=get_system_prompt(),
+        content_text=get_prompt("text_image"),
     )
 
     request_config = {
@@ -356,7 +305,7 @@ def test_text_image_to_text_audio_001(omni_server, openai_client) -> None:
         "key_words": {"image": IMAGE_KEY},
     }
 
-    openai_client.send_omni_request(request_config)
+    openai_client.send_omni_request(request_config, request_num=get_max_batch_size())
 
 
 @pytest.mark.advanced_model