Faint crackling static in KRK Monitors

There's been a faint but noticeable crackle/static coming through my KRK Rokit 5 monitors. They're hooked up through a PreSonus USB Audiobox and 2011 MacBook Pro.

Some more symptoms that I haven't seen anyone else mention with their crackling issues:

- Crackle/static does not increase or decrease volume when I adjust the volume. It stays at a quiet and constant level.
- Happens randomly. I can play songs for hours and the static doesn't get worse. I don't know what triggers it.
- First tried 1/8" cables and now using expensive XLR cables. No change.

Sounds like electromagnetic or radio frequency interference.

The good news: your equipment is not defective.

The bad news: EM and RF interference is very hard to get rid of.

When in close proximity (within a few feet), certain cell phones and other various electronics can cause it when they pull data from the network. If this is the culprit, then you will hear feint pops and hums from time to time (but not all the time).

More than likely it is being caused by bad or just old electrical wiring somewhere in your house. You have a few options in this case (neither of which you'll like unfortunately): you can get an electrician to come out and inspect the building focusing first on the room your equipment is in then going from there. The other option is to purchase a power regulator which will "clean" the power going into your equipment. Power regulators aren't cheap though, usually starting at $350. Also try going around your room and unplugging things one by one (including your laptop if it has a charge in the battery). Sometimes bad or just cheap electrical appliances can cause it too.


The other culprit, radio frequency interference is even more difficult to get rid of because it can be caused by things that are out of your control. If you live near industrial areas or even worse, an airport, then you are out of luck unless you want to spend oogles of money shielding your house from radio frequency waves.

If you're connecting your monitors via RCA cables then try purchasing some shielded cables to see if that helps. If you're connecting via XLR or 1/4 jack connections then refer to the above advice I just mentioned in the last few paragraphs as they are balanced connections and aren't succeptable to interference to begin with.

Good luck!

P.S. Rokit 5's are great monitors for the $$$! That's what I use at home. Good choice on those.

Thanks for the tips. What exactly are "balanced" XLR cables?

All XLR cables are balanced. They're most commonly seen on microphones but other things - including studio monitors - use them too.

This is what they look like:
CBI MLN Performer Microphone Cable at zZounds

I think my issue is the MacBook itself. After months of changing out cables, power sources, etc. I realized the static sound increased/decreased based on where my 2011 metal MBP's screen was positioned.

I saw this happening to someone else on another forum. So how can I fix this issue? Would different monitors work any differently?

rsherid said:

I think my issue is the MacBook itself. After months of changing out cables, power sources, etc. I realized the static sound increased/decreased based on where my 2011 metal MBP's screen was positioned.

I saw this happening to someone else on another forum. So how can I fix this issue? Would different monitors work any differently?

Click to expand...

It's entirely possible for computers to give off interference though they're not supposed to. All electronic devices from appliances to computers are supposed to meet certain FCC requirements on acceptable levels if interference (EM and RF) they emmit before they can be sold but every now and then, one gets through the assembly line that isn't on the level it should be.

The power supply unit (or PSU) could be giving off the interference or it could be the power supply for the LED backlight, the charger, etc. It's really hard to say. Any old transistor in there could be the culprit.

Different monitors might help if they are shielded better. It's really hard to say though.

Are you guys hearing more of a buzzing sound? That's EM (electromagnetic) interference caused usually by electrical equipment and bad wiring somewhere.

Are you hearing faint static that comes off and on? That's RF (radio frequency) interference caused by radio frequencies being picked up by your equipment. Sometimes you can even hear faint voices in there too. Note: it's not just radio stations that cause this but anything dealing with the FCC spectrum; radio, TV, cell phones, etc. all can cause RF interference.

Are you hearing continuous (very) faint static? That's normal. Especially if the volume is all the way up.

Solved Faint Static By Changing Connection

I know this is an older thread but I just experienced the problem with KRK VXT4 monitors and found a solution, inspired by the earlier posts. I solved my issue by feeding the speakers through my good old Alesis USB mixer instead of through a direct connection through the headphone output of the iMac. They are whisper quiet now except for the beautiful sound that is supposed to be coming through and no interference.

Background:
Initially, I connected my speakers through my small Alesis mixer and there was NO static. Since I was just setting up my home workstation environment, I wanted to see how the sound and volume would be if I connected directly through the headphone output of my iMac. I didn't immediately notice the static, perhaps because I was enjoying the music. Only when I stopped a track did I notice the crackling static. As soon as I disconnected the jack from the computer, the speaker went silent. I turned off the speakers. Connected and powered up my USB connected (to the computer) mixer and turned on the KRK VXT's. Beautiful. Not a sound. I couldn't even hear the faint hum of powered monitors.
I am neither a sound engineer nor exceptionally technical beyond basic understanding. So I can't explain the exact cause of the direct connection interference. But I am very happy to report that simply leveraging the mixer output provided a very satisfactory solution.