I know this is an old thread, but I hope what I have found out helps someone out there. I had a Samsung Galaxy S3 with 4.4.3. and speech to text always worked for emails and texts. Alltel sold out to AT&T and they sent me an S4 with 4.4.4. and sometimes when generating a message it would capitalize the first letter in a new sentence and sometimes it wouldn't. So, I started calling AT&T, Samsung and Google to no avail, but I kept pestering them, Google mainly and they admitted there was an issue with 4.4.4. and Google Speech to Text and they were working on it,,yeah right. However, they did give me a work around. If you go into Airplane Mode, new sentences after a period will start out in a capital letter. However, if you are generating an email, the very first letter in the first sentence will not be capitalized, but if you are generating a text it will. After that in texts/emails all subsequent sentences after a period will be capitalized. Then, to send the email/text you have to turn Airplane Mode off to send them. Yeah, it's kinda of pain in the ****, but much easier than going back and capitalizing each letter in a new sentence that wasn't capitalized. They, Google, assured me they are working on a patch....we'll see. Good luck to all.