docs: clarify pronunciation dictionaries support Vapi v1 voices only

fern/assistants/pronunciation-dictionaries.mdx

@@ -12,7 +12,11 @@ Pronunciation dictionaries are supported by the following voice providers:
 
 - **ElevenLabs** — phoneme rules (IPA and CMU Arpabet) and alias rules
 - **Cartesia** — "sounds-like" aliases and IPA notation (sonic-3 model only)
-- **Vapi built-in voices** — pronunciation dictionaries via a unified locator
+- **Vapi built-in voices** — pronunciation dictionaries via a unified locator (v1 voices only)
+
+<Note>
+  Pronunciation dictionaries are supported on **Vapi v1 voices** only. Vapi **v2** voices are powered by xAI's Grok model, which doesn't support pronunciation dictionaries yet. For v2 voices, use [speech tags](https://docs.x.ai/developers/model-capabilities/audio/text-to-speech#speech-tags) to control pronunciation and delivery inline in your text instead.
+</Note>
 
 ## How Pronunciation Dictionaries Work
 
@@ -88,7 +92,7 @@ Cartesia pronunciation dictionaries use a `text` and `alias` format. Each entry
 - **IPA notation**: Precise phonetic spelling wrapped in angle brackets (e.g., `"<<ˈ|v|ɑ|ˈ|p|i>>"`)
 
 <Note>
-  Cartesia pronunciation dictionaries are only available with the `sonic-3` model.
+  Cartesia pronunciation dictionaries are only available with the `sonic-3` (or newer) model. In the dashboard, the pronunciation dictionary option only appears once you select a supported model.
 </Note>
 
 ## Implementation
@@ -242,8 +246,8 @@ Cartesia pronunciation dictionaries use a `text` and `alias` format. Each entry
     {
       "voice": {
         "provider": "vapi",
-        "version": 2,
-        "voiceId": "Elliot",
+        "version": 1,
+        "voiceId": "Kylie",
         "pronunciationDictionary": [
           {
             "pronunciationDictId": "pdict_abc123"