New base model iMac Pro. Every couple hours the keyboard goes crazy and adds a bunch of characters or deletes a bunch of characters. Even control-c has been duplicated resulting in a crazy # of pastes. Cannot be stopped by pressing again. Not a single key or group of keys. Even had the keyboard replaced by the Apple store so it's not the keyboard. High Sierra 10.3.2. Anyone else seeing this? Not sure I want to go to 10.3.4. Wondering what that does with the fan issue.