Update devices-sdk-release-notes.md

Author: mswellsi

articles/cognitive-services/Speech-Service/devices-sdk-release-notes.md

@@ -9,13 +9,18 @@ manager: nitinme
 ms.service: cognitive-services
 ms.subservice: speech-service
 ms.topic: conceptual
-ms.date: 08/07/2018
-ms.author: gracez
+ms.date: 05/22/2019
+ms.author: wellsi
 ---
 
 # Release notes of Cognitive Services Speech Devices SDK
 The following sections list changes in the most recent releases.
 
+## Speech Devices SDK 1.5.1:
+
+*	Include [Conversation Transcription](conversation-transcription-service.md) in the sample app.
+*	Updated the [Speech SDK](https://docs.microsoft.com/azure/cognitive-services/speech-service/speech-sdk-reference) component to version 1.5.1. For more information, see its [release notes](https://aka.ms/csspeech/whatsnew).
+
 ## Cognitive Services Speech Devices SDK 1.5.0: 2019-May release
 
 *	Speech Devices SDK is now GA and no longer a gated preview.