Every time I get a message when I'm in-game, my game drops massive amount of frames

Basically, when I'm playing League and I get a message on League itself, Discord, Skype, Origin, TeamSpeak or any other program my game starts to drop massive amounts of frames. I have an excellent gaming PC so running League and another program at the same time shouldn't be an issue I assume.

I play on a 75Hz monitor and have my frames locked at 60 since that's what I've always done so never bothered to change it. I also plat on windowed 1600x900 (old habit). I know there is an option to close the league client when you're in-game, but I 'd rather leave that enabled. And it still doesn't take away the fact other programs can cause massive lag when they are triggered by for example a message or notification.

The only way I can manually fix this is by either closing the entire program or marking the message as read.

Would love if anyone has encountered this problem before or/and how to fix it.

Greetings!