sometimes a keyboard has a limitation... for instance, i can only press 3 keys on mine at once. another one i used only allowed me to press 2 keys at once. after updating the driver for that keyboard i was able to do more. i don't think its a bug. especially since its a new setup you are running. i suggest trying to get the latest driver for your keyboard. if it is bluetooth, latest driver for that. if it's usb, make sure your motherboard usb drivers are up to date. if you do all of that in that order and still no luck, try a new keyboard.