Very slow speed when crouched

Put the summary of the bug you're having here

What I expected to happen was...:
I expected to be able to walk at a normal (crouched) pace while crouched.

What actually happened was...:
Now, when crouched, my pace is so slow, I spend twice or thrice the time to build a roof or lay minecart tracks as I did prior to the last update.

Steps to Reproduce:
1. Launch game.

2. Engage crouch mode/ left shift to crouch player.

3. Attempt to walk.