Grounding problem

[electricsmooth]

I have an NS7ii (with screens, so basically a NS7iii). Ever since I added the screens, I've been getting grounding issues. The screens have a separate power supply to the controller. I tried the Numark forums but they forwarded me a link for grounding issues in general and not specific to that device.

So what will happen is that when I connect something to the unit after it is up and running (USB drive to the computer, Headphones, phone to the Aux) it will sometimes become unresponsive and I have to reboot everything. This is fine at home but at an event- highly embarrassing.

Any suggestions on what to do? I suppose I can always just disconnect the screens but then there is no use of even having them.

[djpenguin]

Do you have pictures and/or diagrams of the changes you made?

[electricsmooth]

No, sorry. Basically, the screens have their own (2 prong ) power supply which is separate to the controller's power supply (3 prong). They connect to the controller via USB. I plug both power supplies into the same power strip/power bar along with the laptop's power supply.

[djpenguin]

With such vague information, it's very difficult to give any sort of detailed advice.

Basically, if the device worked before you modified it, some part of your modification is causing the problem. Now you need to troubleshoot the modification to try to find the issue. Connect or activate one small piece of the modification at a time and see where the trouble appears. When you know what part of the system is causing the problem, you'll be able to start figuring out how to fix it.

[andymunro]

Rather than a modification, I think it's the screens that are part of the package, they have a separate power supply.



I'd contact Numark and see what they recommend.

[electricsmooth]

Yeah, that's exactly it. I did contact Numark and they don't seem to have any real answers. They provided a generic link for grounding issues for audio systems but nothing specific to this controller.

[andymunro]

That's strange, the only thing i could recommend trying is a ground loop isolator that was recommended on here recently to someone having issues with a laptop, put it inbetween your audio out and the amplifier and see if that removes the buzz.

[electricsmooth]

The thing is, there is no buzz. It performs great sonically. The problem is something completely different. When I connect something to the controller or the laptop (headphones, USB drive, phone), occasionally it will cause the whole system to freeze. I have to reboot everything. It's like a build up of static or something.

[andymunro]

In my amateur electronics experience, I'd say it's more likely to be soft/firmware related. Have you tried up****** the firmware?

[djpenguin]

My apologies, I thought it was a modification because of the section. Luckily, some of the same troubleshooting principles still apply.

Does the issue appear only with the screens fully connected? Can you replicate the issue if the screens are only connected via USB (no power)? Can you replicate the issue if the screens are only powered (no USB)?

There are a lot of things that could potentially be going wrong. If you've given up on support from Numark, you'll need as much information as possible to isolate and solve the problem.