going crazy trying to sort this out, just got a new windows 10 pc build from someone. been using a scarlett 18i8 with a mac for a long time which worked fine. whenever I plug it in to the pc I get erratic crackling. its not super loud, just irritating. I can deal with minor hum because its constant but the crackling is driving me mad. I tried other USB ports, different wires, I tried plugging the interface wall plug into a separate jack, changing sample rates and buffers etc, installing drivers.
eventually I realised it happens when I plug the usb in even when the interface is off. it gets worse when I turn it on, but its there whenever its plugged in. not sure what to try as I already plugged the power into a separate wall socket
Yeah it’s seemingly not software related but my interface is fine on my laptop. I just managed to make the crackling a bit quiter by using shorter audio cables so I’m thinking the pc having extra juice is being picked up more easily by my wires. Time to switch to XLR I suppose, wouldn’t have thought it necessary on such a short cable but it’s markedly quieter now. Will do for the time being.
If you’re sure it’s not sample rate, constant hum + crackling could be due to a bad power supply unit (very usual on cheap PC)
Your place may have ground issues or wrong wiring/too much devices on the same line/circuit breaker.
Since your laptop works on battery (even if plugged), it’s not sensible to voltage peaks, current surges and noise.
Does your pc have a metal casing? If so, try to “ground” the pc by wireing the case to something metal (heating pipe). Or touch the casing of the Scarlett to see if the noise is reducing. Disconnect other USB peripherals can also help.