http://feedback.dayzgame.com/view.php?id=2049
This link is also the same problem but mark as revolved. But it is not revolved at all.

I am definitely experiencing the character completely stopping when changing weapon. Not only weapons but also the compass.

For clarity:
This happens only with raised weapon/hands/compass/etc!

Steps:

1. Take any weapon in hands.
2. Raise weapon (with Space key).
3. Start to run (with W key).
4. While running change weapon using hot-key.
5. *** Observe character stopping and weapon changing animation.

!!! If you do it with lowered weapon/hands no stopping occurs.