In normal mode, press and hold the S button.
To adjust the real-time display, follow these steps while in normal mode: nako na-613d manual
Press the M button three times. The seconds should start flashing. In normal mode, press and hold the S button
To switch between TV mode, HDMI, or USB: In normal mode
Because specific physical manuals for smaller brands are rarely indexed online, I have compiled a below based on the standard technical specifications and operational procedures for the NA-613D chassis.
The following is a generic guide. Refer to your actual manual for exact button functions.
(assuming a 5-star rating)