3dscapture.com

After searching through the forums and elsewhere online for quite a bit of time, I'm still not really sure how to solve this issue. Essentially, I'm having some pretty bad audio issues. Might as well go ahead and give an example of some raw footage before I get into the nitty-gritty: https://www.youtube.com/watch?v=LPnF6RrM54Y

If I have the line-in plugged in without the USB, the audio quality is perfect. When I plug in the USB cable, the audio has a quiet layer of white noise (which I do believe the filter might fix, but I need to buy one). When I start the 3DS capture program, I get that final layer of buzzing, which overpowers everything. If I close it, it goes away. I tested recording the line-in with Audacity with the 3DS capture program closed, and the audio is fine (albeit with that quiet layer of white noise if the USB cable is plugged in). I've tried everything from using different versions of the 3DS capture program (including the beta version that supports 3D video capture) to using different USB ports to changing the volume slider on the 3DS itself. Can't pinpoint what's going on. Any help would be greatly appreciated.

Well, you mentioned that you didn't have the filter. I believe the tones you're hearing are what the filter will remove.

Without it, you could use software to remove the noise. For constant tones like that, a program like Sound Soap, or the noise removal/repair in Adobe Audition would work wonders. They take samples of the tone and do a good job of removing it.

That sound however, does sound like interference or ground loop noise. The removal of the USB plug (and subsequent lack of noise) also points to software not being an issue at all.

The only thing is that that really bad buzzing sound only happens when the 3DS capture program is opened. Otherwise, it's not there. That leads me to believe the filter wouldn't do anything to help that particular issue. That small amount of white noise (i.e. a different sound than described above) is fixed when the USB cable is removed. I can understand the filter helping with that.

EDIT: Of course, I will pick up a filter tomorrow and report back, but I was wondering if there's another underlying issue I should know about.

I misread your OP with regard to the capture program, sorry.

Have you tried just monitoring the audio from the 3DS with headphones while using the capture program and/or just having it plugged in? Just a thought.

Yes, it's ground loop noise, as sticktodrum says. I'm guessing you bought it second hand? I include a filter with every board I send out. The noise is louder while the program is running because there's more USB activity.

I did buy it second hand, yes. If I implied that you forgot to include a filter, I'm sorry.

Is there anything I can do to eliminate that sound? If that's something the filter would have eliminated, I'm sorry for even bringing this up.

Yes, a filter will fix it. Something like this or this.

Or you can try doing noise reduction in software. Or record the audio with a different computer.

Thanks for all the help, guys. I really appreciate it.