First of all I would like to thank you for purchasing the G15 keyboard. Regarding the backlight flickering problem, I would recommend to try using different usb ports or test the keyboard on different system to determine whether the keyboard is defective.
If the G15 keyboard is proven to be defective, I would suggest to contact our helpline support for a replacement at the following numbers listed below :-
Customer Support United States 702-269-3457 Mon - Fri, 6am - 6pm PST Canada 416-207-2782 Mon - Fri, 6am - 6pm PST
For more information on the replacement procedure kindly click here