Have you tried to change the refresh rate, and does it make any difference? Also, if the problem is persisting, please close the game, delete the client_settings.ini file and restart the game. This should recreate a new version.
Tried changing the refresh rate. Same results.
Deleted the .ini file... A new file isn't created and now the game client crashes with an error code C5 as soon as it is launched from the launcher. It doesn't give me a new client_settings.ini file either. Thankfully I kept a copy on my desktop.