Modifying powercords

[E-Stat]

... my powercords run down about 3 inch (10 cm) behind the back of my screen. My screen starts to flicker a little as soon as I switch on my amps, so there is some interference visible.

I would start by isolating signal wires, be they for a computer monitor or audio interconnects, from the power cords. You might try using plastic conduits to separate the two. Also, you might want to experiment with your component placement. Power amplfiiers with their larger power supplies need more space between them and sensitive electronics. If practical, put them on top of other components rather than the other way around. Although I generally do not recommend power conditioning devices for use with receivers, amps, and the like, your environment may benefit from them.

I might go for plan B: an isolation platform under my components, maybe this prevents my screen from flickering.

While I believe there can be audible benefits from mechanical isolation devices, I doubt they would help with your screen flicker.

rw