Re shielded cable... not recommending this, not not recommending this, just telling the story. Many years ago in the office at work I had a Mac and a PC. I only wanted one monitor and one keyboard in front of me so we bought a switchbox. Big, expensive, relatively low-tech clunker of a unit. Anyhow, I kept getting ghosting on my monitor. I read up on it, asked questions to I/T, etc. No store-bought solutions available that weren't gawdofful expensive. Budget-approvers would not OK anything else for me because I was done, right? One monitor and one keyboard. No more purchases.
I ended up making my own shielded cable. I applied something to make the shield stand off the cable, then I wrapped it with tinfoil -- once? a few times? I don't remember. Then I attached a ground wire to the tinfoil at the plug end which attached to the center screw at the outlet. Then I wrapped the cable with tape. About the fugliest thing you've ever seen. It either worked well enough or I put so much effort into it that I forced myself to think it did! Anyhow, I lived with it for a good while. Later prices came down for better, smaller, factory-made compatible components all around. This was a long time ago.