An awesome student from our education program made this wiki. It is not managed by iFixit staff.
Numark N4 Troubleshooting
Entry level DJ controller released in December, 2011 with a bar code identification number (21)N31202191407364.
Device won't turn on ¶
The Numark N4 will not respond or show any sign of powering up
Faulty Main PCB Circuit Board ¶
If the device is not showing any sign of powering up, it is possible that the main circuit board is damaged. A main circuit board replacement guide can be found here Numark N4 BP Main PCB Board Replacement.
Faulty Power Adapter ¶
It may simply be that your main power adapter is damaged. Consider purchasing a new one.
Sound is not working ¶
There is no sound being produced from the speakers that the Numark N4 is attached to.
Improper Settings ¶
First, connect your N4 controller to your computer. Click the Windows start button and search for "Sound". Open the "Sound Preference" window. Navigate to the playback tab and make sure that your sound-producing device is set as the default playback device. Launch Serato DJ.
Faulty Audio Jack ¶
First, make sure that the cables are firmly plugged into the audio jacks. Audio that sounds distorted can be a sign that your audio jacks are too loose. If there is visible damage, consider replacing the audio jacks. A guide can be found here Numark N4 Audio Jack Replacement.
Jog wheels are over-sensitive ¶
When the Numark N4 is set to scratch mode, moving your finger near it can cause the music to stop.
Unit Not Grounded ¶
To test if this is the source of your problem, touch the earth pole on the back of the unit and simultaneously scratch the other side of the jogwheel. You need to ground the unit by attaching a wire to this pole while this action is performed. Digital DJ tips has an excellent video, the link to which can be found here https://www.youtube.com/watch?time_conti....
The buttons, knobs or sliders are not working ¶
Various buttons, knobs, or sliders are visibly damaged, or simply unresponsive.
Faulty PCB Circuit Board ¶
If the majority of buttons are not responding, it is possible the PCB circuit board underneath that corresponding location is damaged. A guide on replacing it can be found here Numark N4 PCB Circuit Board Replacement
Damaged Effect Button ¶
It is possible the plastic connector for the effect button is not reaching the circuit board properly. If a effect button is visibly damaged or unresponsive, a guide on replacing it can be found here Numark N4 Effect button cover Replacement.
The USB not recognized by Numark N4 ¶
The USB port is not responding or visibly damaged.
Faulty USB ¶
If the the USB port is unresponsive, a guide on replacing it can be found here Numark N4 USB Port Replacement.