Thanks for playing! Someone reported this problem before in the threads, not sure what causes it. Can you try setting AlternateSyncMethod to 1 in the options .ini and seeing if that fixes it? I'm honestly not sure if it's my inept programming or something to do with GMS.
It seems to run fine on my friends computer, and that fix didn't work :(. One random comment from friend: enemy explosions are kinda big and cover up enemies and bullets so you can't see what's going on.