Reddit mentions of Compact Mini Hum Eliminator Box - 2 Channel Passive Ground Loop Isolator, Noise Filter, AC Buzz Destroyer, Hum Killer w/ 1/4" TRS Phone, XLR Input/Output, Uses 1:1 Isolation Transformer - Pyle PHE400

The source is the computer. I had the same issue when I hook HS8S (subwoofer). The solution is Balanced cables + all your power comes from one outlet. I also added recently this, https://www.amazon.com/gp/product/B00BARTW42/ref=od_aui_detailpages00?ie=UTF8&psc=1




Good luck

I found the advice on this sub to be wrong for my noise issues with my JBL 305s.

The sub said that the 3.5 mini jack to 1/4" TR was to blame and that I had shitty motherboard audio, and so I went with a Focusrite 2i2. Most of my noise was gone, but under video card load I'd get a ton of it back. The USB still shares the same ground loop issues no matter what I did to fix (pull ground pin, isolate USB ground, and tried different power supply).

In the end, what solved my problems was a Pyle Pro Hum Eliminator. The noise is gone with and without the DAC. So in the end, ground isolation is what I needed, not a DAC. I'll probably keep the DAC just because I like the expensive physical volume knob, but it wasn't the solution.

To add, I have my JBL 305s at Volume 5, PC Volume for USB Focusrite volume at 100, and my Focusrite's physical knob between 9 o'clock and 11 o'clock most of the time.

The issue is that studio monitors are generally designed for balanced connections (XLR/TRS), and you are adapting an unbalanced connection (3.5mm/RCA). When using unbalanced cables, you risk picking up interference, especially in an electrically noisy environment (like a computer).

Basically, your computer puts out a lot of electrical interference, and the 3.5mm jack on your motherboard is not correctly shielded from this interference. The issue is not your wall sockets or your placement, it is inherent to the source.

My suggestion would be to either get an audio interface that supports balanced connections, or try an inline hum eliminator.

That's what solved it for me. Although I used this. If you wan't XLR it looks like you could save $70 and buy this.

Thank you! It's all starting to make sense now, with the Profire out of the way. This RCA cable is what I have and what I thought I was expected to use. Now I understand, rather, that it's a red/white RCA to red/white RCA with 2 TRS adapters, one for each monitor. Makes perfect sense.

I do have two additional TRS cables as well, however they cause the humming, so for some reason I thought perhaps the RCA would be a solution, but since those run to an adapter which converts to TRS, it seems like that will lead to the same humming/buzzing.

Before going to sleep last night, I purchased this hum/noise eliminator, and an additional two TRS Cables.

With this, I believe I have two options. I can run these two 3" TRS from the DDJ to the hum/buzz eliminator, then directly into the Yamaha's INPUT 2, while keeping my Profire connected to input 1, thus allowing sound from both sources (is this a problem?).

Option 2, would be to run the 3" TRS cables from the DDJ to the Profire inputs, along with my PC running to the profire via USB, then the profire would output to the hum/buzz eliminator, which would then output to the yamahas (so the Yamaha's would have only 1 input). The benefit here would be eliminating the terribly common buzzing that comes from BOTH my desktop, and the DDJSR

What about this: https://www.amazon.com/gp/product/B00BARTW42/ref=oh_aui_detailpage_o00_s01?ie=UTF8&psc=1

?

Sources of audible hum include other devices connected to the same socket, EMI from nearby appliances, and being close to a power line. If you've ruled all these out, the monitors themselves could be faulty. Can you get them serviced? If not, depending on the source, you can try to get a mains hum filter like like this isolator box here (this one works on the audio output side though and not the power supply so ymmv).

If you're a DIY type, filter capacitors on the circuit board can fail and give rise to power line hum. You can replace these cheaply.

I've seen a number of people having this issue, it's a big reason I'm looking at getting Airmotiv 4/5S instead... One person did say they bought this and wired it in, which solved the problem for them:

http://smile.amazon.com/dp/B00BARTW42/ref=wl_it_dp_o_pd_nS_ttl?_encoding=UTF8&colid=3IZ89HWZPWPP5&coliid=I3DRFTIT92XDX6

edit: Some relevant threads:

https://www.reddit.com/r/audiophile/comments/3p0tr4/lets_figure_out_jbl_lsr305_hissing/

https://www.reddit.com/r/audiophile/comments/2r0skn/very_audible_buzzing_noise_from_jbl_lsr305s_when/

https://www.reddit.com/r/audiophile/comments/441cy0/jbl_lsr305_hiss/

These are new. I’ve tried all sorts of stuff to eliminate the buzz/squeal you hear ahead of time. Tried power strips, different outlets, etc.

If the TRS cables are not plugged in to the speaker, but it is powered, it remains silent. Further, as you can see in the video, it intensifies when using certain apps, such as the game Hollow Knight.

Any direction or wisdom?

Edit: I should add that I’m running these through an m-audio 2x2 USB interface.

Edit 2: Updating resolution. Purchased a compact mini hum isolator from Pyle. https://www.amazon.com/dp/B00BARTW42/ref=cm_sw_r_cp_api_i_i9E3Cb7892HXW Hooked it up and it works great. No more hum/buzz!

I found this the other day and ordered from research it work incredibly


Compact Mini Hum Eliminator Box - 2 Channel Passive Ground Loop Isolator, Noise Filter, AC Buzz Destroyer, Hum Killer w/ 1/4" TRS Phone, XLR Input/Output, Uses 1:1 Isolation Transformer - Pyle PHE400 https://www.amazon.com/dp/B00BARTW42/ref=cm_sw_r_cp_api_i_Sv7EDb9PN2N9Z

yeah, you should be able to use the DAW eq, and cut the high and high-mid levels til the hum/hiss goes away a bit, then record. then after the track is recorded, take and put the highs and high-mids up again. that might do the trick.
however, an easier way to do this is to get a DI box that has a ground switch on it. the grounding in those DI boxes can really help to kill hum by creating a reverse feedback loop of the hum that will cancel out the original hum, without affecting the sound of the mic itself. so you would go mic-> DI box-> interface. you can get one pretty cheap on amazon. like 20-30 bucks for a decent one. there are other devices that can also help you out. here are some of them:

DI box:
https://www.amazon.com/gp/product/B000CCSWQA/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1
....

in-line hum killer:
https://www.amazon.com/Hosa-GLT-255-Female-Ground-Stopper/dp/B00FC4YPL4/ref=sr_1_1?gclid=CjwKCAjwwvfrBRBIEiwA2nFiPYLmaB4BVKR6rNWVzM6W-E3Bqtg5P3KDDo648AMCk-n5ct-CQRdroBoCTrMQAvD_BwE&hvadid=345591872771&hvdev=c&hvlocphy=9003283&hvnetw=g&hvpos=1t2&hvqmt=e&hvrand=1374900578903071298&hvtargid=kwd-300662784413&hydadcr=29836_10192790&keywords=hosa+glt-255&qid=1568587585&s=gateway&sr=8-1
...

hum stopper box:
https://www.amazon.com/PYLE-PRO-PHE400-Eliminator-2-Channel-Outputs/dp/B00BARTW42/ref=asc_df_B00BARTW42/?tag=hyprod-20&linkCode=df0&hvadid=312305907549&hvpos=1o16&hvnetw=g&hvrand=3250323847603544719&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003283&hvtargid=pla-406164115673&psc=1



and heres some sites to read as well:

http://recordinghacks.com/2013/02/18/fixing-microphone-hum/

...

https://www.techhive.com/article/3063590/how-to-get-rid-of-hum-and-eliminate-other-noises-from-your-audio-and-video-systems.html


good luck!