1 files changed, 16 insertions, 3 deletions
diff --git a/audiobook.py b/audiobook.py
index 302bb17..a610caa 100755
--- a/audiobook.py
+++ b/audiobook.py
@@ -394,9 +394,22 @@ def convert(backend: str, voice: str = None, clone: str = None,
                 print("[INFO] Conversion cancelled; nothing was converted")
                 return 0
     else:
-        # qwen: instructions design the voice (VoiceDesign model), a
-        # reference .wav clones one (Base), otherwise a built-in speaker.
-        if (instructions or "").strip():
+        # qwen: a built-in speaker (CustomVoice — with the instructions
+        # text, if given, sent as that model's delivery/style control), a
+        # reference .wav clone (Base), or instructions alone designing the
+        # voice (VoiceDesign). Instructions never *switch* the mode:
+        # speaker+instructions is a directed CustomVoice run, and
+        # clone+instructions is refused — the Base demo has no
+        # voice-direction route, so silently redesigning the voice would
+        # drop the chosen reference.
+        wants_instructions = bool((instructions or "").strip())
+        if clone and wants_instructions:
+            raise ValueError(
+                "The qwen-tts Base (voice cloning) demo cannot take style "
+                "instructions. Drop --instructions, or pick a CustomVoice "
+                "speaker with --voice (which sends them as delivery "
+                "control) or the VoiceDesign model (--instructions only).")
+        if wants_instructions and not (voice or "").strip():
             voice_mode = VOICE_MODE_DESIGN
         else:
             voice_mode = VOICE_MODE_CLONE if clone else VOICE_MODE_CUSTOM