[BUG] Vayne Auto Attack Not Applying Damage

I've been playing as Vayne and when having a slow attack speed in the early game and attempting to attack move, by canceling the auto attack animation, I've seen the projectile hit a minion and not apply any damage nor bolt. I think the auto attack doesn't complete even if the projectile is already in the air. I'ts kind of annoying when playing with a limited resources PC.

This happens without lag, I play with a constant ping of 80 ms and 60 fps

To reproduce:

• Pick Vayne in Summoners Rift (I use the Dragon Slayer skin)
• Pick Runes with 12 % or so of attack speed
• Get your starting items and auto attack minions with a good amount of distance and when the projectile is in the air, click away to cancel the animation
• With some luck you'll see that the auto attack hits the minion but does no damage.

My PC is an ACER Aspire V3 -471-6867 OS: Windows 8.1 Intel HD Graphics 4000, up to 1760 MB Dynamic Video Memory Intel Core i5 2.5Ghz up to 3.1 Ghz

I play with the grahpics set at the lowest