I have an Auto-Technica usb turntable. After recording from turntable to pc with Audacity I hear a constant buzz/hum through the music. I used a usb cable with a Delock extension cord.
GHeuvel
Noise is an analog problem so the problem is the turntable. This is analog technology and some hum & hiss is normal from a turntable/cartridge/preamp. If you can hear the hum over the music, the turntable may be defective.
Hum originates from the AC wiring all around you so try moving or rotating the turntable to see if that helps. Transformers can make it worse (if your turntable is sitting on top of an amplifier or something with a transformer in it, etc.).
Try the Noise Reduction effect. Get your noise profile with the stylus out of the groove (so you’re not including record surface noise).
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