Cant open inventory when pressing certain keys

*What I expected to happen was that my inventory would open when walking forward and right, or when walking backwards and right. **When walking forward/backwards and left the inventory will open.

*What actually happened was that my computer played an error tone and my inventory did not open.

Steps to Reproduce:
1. Press your forward movement key and hold it down.
2. Press your right movement key and also hold it down
3. Press your inventory key with the other two also held down
Note: W+D+E for most users. W+A+E will work however.