For those of you who don't have access to proper grounding (because, for example, the wiring lacks PE or it's faulty): a plain separation transformer (1:1) betw

For those of you who don't have access to proper grounding (because, for example, the wiring lacks PE or it's faulty): a plain separation transformer (1:1) between mains and your laptop might be able do the trick. Unfortunately if you have a larger setup (speakers, monitor, etc.) you have to connect everything to the separation transformer, otherwise you'll create leakage a path to mains some other way (say, through the audio jack). Caveat emptor: If you decide to go that route, make sure you can return the transformer if it doesn't to the job.