What keyboard do you have? I’ve seen some people have similar problem and when they’ve turned off Synapse it stopped double typing.

Yes, I have encountered the issue of double typing on my Razer Keyboard. It can be quite frustrating when keystrokes are registered twice instead of once. I've tried troubleshooting by updating drivers and firmware, but the issue still persists. Has anyone found a solution to this problem? Any advice or suggestions would be greatly appreciated.

I’m also experiencing this issue and my keyboard is just outside of warranty. I have not found a resolution and I’m not using Synapse as I’m using the keyboard on linux. What if anything is Razer doing?

Here is another occurrence: https://www.reddit.com/r/razer/comments/837rey/my_razer_keyboard_double_typing_on_many_keys/

I have the same issue too, Razer Pro Type..  Love it as its one of the solid white mechanical keyboards.. 

Bought the SAME one.. second time.. same issue. Very upset!