diff --git a/lib/Service/OpenAiAPIService.php b/lib/Service/OpenAiAPIService.php
index b28c4e42..b8e79328 100644
--- a/lib/Service/OpenAiAPIService.php
+++ b/lib/Service/OpenAiAPIService.php
@@ -560,7 +560,7 @@ public function createChatCompletion(
 						'type' => 'input_audio',
 						'input_audio' => [
 							'data' => $userAudioPromptBase64,
-							'format' => 'mp3',
+							'format' => 'wav',
 						],
 					],
 				],