Does your table have a ground wire, and if so, is it hooked up to your receiver or phono amp.
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Quick sidenote, that would be the "topology" or how things are connected, not topography,which describes the form of the earth's surface.
The phono or wires connecting it may be picking up radio frequency RF noise from the nearby digital gear. Move the wires slightly while connected and see if the sound of the noise changes. If it does, then bingo.
Are your interconnects shielded? If not, shielded ICs might resolve the problem if it turns out this is what it is.