diff --git a/app/services/llm.py b/app/services/llm.py
index fca6bcaf..49d552f9 100644
--- a/app/services/llm.py
+++ b/app/services/llm.py
@@ -5,6 +5,8 @@
 from loguru import logger
 from openai import OpenAI
 from openai import AzureOpenAI
+from openai.types.chat import ChatCompletion
+
 from app.config import config
 
 
@@ -133,7 +135,15 @@ def _generate_response(prompt: str) -> str:
             messages=[{"role": "user", "content": prompt}]
         )
         if response:
-            content = response.choices[0].message.content
+            if isinstance(response, ChatCompletion):
+                content = response.choices[0].message.content
+            else:
+                raise Exception(
+                    f"[{llm_provider}] returned an invalid response: \"{response}\", please check your network "
+                    f"connection and try again.")
+        else:
+            raise Exception(
+                f"[{llm_provider}] returned an empty response, please check your network connection and try again.")
 
     return content.replace("\n", "")
 
diff --git a/app/services/subtitle.py b/app/services/subtitle.py
index 5ea80286..d19ac59a 100644
--- a/app/services/subtitle.py
+++ b/app/services/subtitle.py
@@ -1,4 +1,5 @@
 import json
+import os.path
 import re
 
 from faster_whisper import WhisperModel
@@ -17,8 +18,13 @@
 def create(audio_file, subtitle_file: str = ""):
     global model
     if not model:
-        logger.info(f"loading model: {model_size}, device: {device}, compute_type: {compute_type}")
-        model = WhisperModel(model_size_or_path=model_size,
+        model_path = f"{utils.root_dir()}/models/whisper-{model_size}"
+        model_bin_file = f"{model_path}/model.bin"
+        if not os.path.isdir(model_path) or not os.path.isfile(model_bin_file):
+            model_path = model_size
+
+        logger.info(f"loading model: {model_path}, device: {device}, compute_type: {compute_type}")
+        model = WhisperModel(model_size_or_path=model_path,
                              device=device,
                              compute_type=compute_type)