Ults Flying Backwards!

This bug is really annoying and can result in the loss of teamfights and games. I've gotten it playing Nami and Aurelion Sol , 2 champs with ults that are skillshots. Here's what's happening.

There's a teamfight, the enemies are bunched up, I figure it's a good time to hit them with the ult damage. For Nami, I aim the ult at them and press R...it goes in the opposite direction. I figure "maybe my mouse was on the minimap and I didn't realize it". So I tell myself to be more careful. Playing Nami again, another teamfight, same result as before. I know I was more careful about this ult, so I'm suspicious of the 180 degree turn of the wave. Now I'm playing URF as Aurelion Sol. There's a teamfight in the jungle. The enemy team is jumping on our Riven, she's tanking. I figure its a good time to hit them with the dragon ult. I carefully aim it this time to make sure I get as many people in it as I can, its got a smaller width than Nami's ult after all. My mouse is dead in the center of the fight. I Press R (quickcast) and the ult flies off backwards into some other bush. We all die. No one commented on it thankfully, but I was really mad! I know it wasn't me that time, I was careful!

So there you have it. It's not every game, but lately I've been getting these backwards flying ults and they ruin games for me. Riot please fix them so I may dragon like a snake and ks the cutest fish.