diff --git a/app/services/grok/utils/process.py b/app/services/grok/utils/process.py
index 378aefd..4ad7c7a 100644
--- a/app/services/grok/utils/process.py
+++ b/app/services/grok/utils/process.py
@@ -84,6 +84,16 @@ async def _with_idle_timeout(
         idle_timeout: 空闲超时时间(秒)，0 表示禁用
         model: 模型名称(用于日志)
     """
+    try:
+        idle_timeout = float(idle_timeout or 0)
+    except (ValueError, TypeError):
+        idle_timeout = 0.0
+
+    try:
+        first_item_timeout = float(first_item_timeout or 0) if first_item_timeout is not None else 0.0
+    except (ValueError, TypeError):
+        first_item_timeout = 0.0
+
     if idle_timeout <= 0:
         async for item in iterable:
             yield item
diff --git a/app/static/public/js/video.js b/app/static/public/js/video.js
index bdc979a..12dd44e 100644
--- a/app/static/public/js/video.js
+++ b/app/static/public/js/video.js
@@ -843,7 +843,7 @@
       },
       body: JSON.stringify({
         prompt,
-        image_url: imageUrl || null,
+        image_url: parentPostId ? null : (imageUrl || null),
         parent_post_id: parentPostId || null,
         source_image_url: parentPostId ? (resolvedRef.sourceUrl || imageUrl || null) : null,
         reasoning_effort: DEFAULT_REASONING_EFFORT,