I have also had this issue was more then 2-3 times for me current branch is unplayable with this bug needs fixing ASAP before we can efficiently test other features.

hit alt key twice ftw maybe?
pressing alt allows you to turn your head, hitting it twice locks that

or is it that you walk without having a key pressed?

Look at the video 0:17 https://www.youtube.com/watch?v=S-4KDETLOPg&feature=youtu.be
Yes you are walking without pressing a key

Can confirm, movement gets locked until you press the key in which you're moving. Doesn't fix it all the time though. Movement locks in each direction, including diagonal. Happens entirely too often.

On a related note, occasionally movement is delayed a half second or so after pressing a movement key.

Same problem here -> http://feedback.dayzgame.com/view.php?id=17574

I can confirm this movement lock is happening as well.

If you double tap the direction you're stuck moving in, it will stop. Stopped it every single time I did this.

That's right. Double click W stops the movement. But the key has not been used by me. Fast Forward is with me on left STGR.

confirmed

Hey guys,
thank you for the information, I decided to use the #17595 ticket for this issue, please refer to it to provide further details.
Thank you,
Andy