diff --git a/server.py b/server.py
index f198562..4f533e5 100644
--- a/server.py
+++ b/server.py
@@ -354,6 +354,14 @@ def _start_srt_transcoder():
                 _transcoder_last_error = str(e)
                 break
 
+        # Log any ffmpeg stderr output to help diagnose failures
+        try:
+            err = proc.stderr.read().decode(errors='replace').strip()
+            if err:
+                print(f'[FFMPEG SRT] {err}')
+        except Exception:
+            pass
+
         if proc.poll() is None:
             try: proc.terminate()
             except: pass