diff --git a/src/assistant/lib/tts/models/protocols.py b/src/assistant/lib/tts/models/protocols.py
index 5774c08..1912cce 100644
--- a/src/assistant/lib/tts/models/protocols.py
+++ b/src/assistant/lib/tts/models/protocols.py
@@ -4,11 +4,13 @@ import lib.models as models
 
 
 class TTSRepositoryProtocol(typing.Protocol):
-    def get_audio_as_bytes(self, request: models.TTSCreateRequestModel) -> models.TTSCreateResponseModel:
+    async def get_audio_as_bytes(self, request: models.TTSCreateRequestModel) -> models.TTSCreateResponseModel:
         ...
 
-    def get_voice_model_by_name(self, voice_model_name: str) -> models.BaseVoiceModel | None:
+    async def get_voice_model_by_name(self, voice_model_name: str) -> models.BaseVoiceModel | None:
         ...
 
-    def get_voice_models_by_fields(self, fields: models.TTSSearchVoiceRequestModel) -> models.LIST_VOICE_MODELS_TYPE:
+    async def get_voice_models_by_fields(
+        self, fields: models.TTSSearchVoiceRequestModel
+    ) -> models.LIST_VOICE_MODELS_TYPE:
         ...