Galaxy S6...The mic on the text keyboard can no longer be set as a default after marshmallow update

[AC Question]

Galaxy S6. Why can I no longer set the microphone as the default in the text app? If I have the microphone set when I start texting and then I choose an emoji and then back out of the keyboard, it stays on the emoji icon. In the past it would go back to the default which I set as the microphone. Now every time I want to use speech, I have to long press the emoji icon to change it back to the microphone every single time. And if the Emoji is the last thing I use, and I close the text app and go back to it later and want to send a new text, when i open texting, it's stays on the emoji icon because it was the last thing I used. Now I have to again long press the emoji icon to change it back to microphone. Where on the phone can you set the microphone as the default so I don't have to keep changing it back to the microphone after using the emoji icon?