Unwanted noise making its way into your monitors is a common support question, and it's almost always solvable. Here's how we like to approach it.
The Gold Standard Fix
The ultimate solution is to run a dedicated DAC or audio interface with balanced XLR or TRS cables to your monitors. Keeping the signal digital until it leaves your computer, then converting it cleanly through a quality interface, eliminates the vast majority of noise issues before they start.
Many entry level options will get you near professional-level, low-noise audio without a major investment. Using an interface and balanced cables is what the pros do!
Common Noise Sources, and what to do about them!
Computer Noise / GPU Coil Whine
This sometimes affects our gamer friends - and it’s usually the result of an unbalanced RCA or 3.5mm connection running directly from a computer or gaming console to your monitors. The tell-tale sign: the noise changes when you move your mouse or the GPU is under load. Fix: Add an interface or DAC to keep the signal digital until it’s outside the computer.
USB Noise
Some PCs have inherently noisy USB outputs, we’ve seen it from custom wiring or just the nature of certain hardware. If troubleshooting keeps pointing back to a specific USB port, a USB isolator is a simple and inexpensive solution worth trying. You could also add an interface and run balanced cables… just sayin’!)
Ground Loop
Caused by interconnected gear drawing power from different points on your circuit, creating a hum that travels through the signal path. Try a ground lift to isolate the offending piece of gear. Process of elimination is your friend here. Usually, drawing power from one outlet and using a quality surge protector here is a good move!
EMI / RFI (Electromagnetic or Radio Frequency Interference)
Nearby power cables, electronics, or wireless devices can emit fields that penetrate unbalanced cables and show up as noise in your monitors. Balanced cables are largely immune to this. Another reason we're such fans of running XLR or TRS.
TS vs. TRS — Are You 1000% Sure?
If you're using 1/4" cables, double-check that they're TRS (Tip-Ring-Sleeve) and not TS (Tip-Sleeve). TS cables are unbalanced instrument cables — they'll carry audio, but they won't give you the noise rejection of a true balanced connection. Look for three conductor sections on the plug, not two. The T, R and S are functionally equal to the three pins you see on an XLR cable.
Side note: Using TS on an input that is expecting a balanced TRS signal may also result in a loss of level by up to 6dB.
A Note for First-Time Studio Monitor Owners
If this is your first pair of studio monitors, it's worth mentioning that no studio monitor is 100% silent at idle. Cleaning up your signal path and obeying good fundamentals will take care of most noise issues, but any time you combine an amplifier with high-sensitivity drivers, a slight noise floor will be present when no signal is playing. It's a performance tradeoff made in favor of accuracy, and it exists across every brand and design at every price point.
We have dedicated articles about Self Noise / Noise Floor, Signal to Noise Ratio and more to help discuss just about anything you might encounter when working with studio monitors of any kind.