Ordered a Pink Faun LAN Isolator and got it yesterday, and at least in my setup it improved the sound very noticeable. It gave a combination of deeper silence, more details and yet a more comfortable sound with less harsh high frequencies. It also gives the impression that the volume is slightly lower, which of course it isn’t but it probably feels that way because some sound that was not supposed to be there got removed.
The LAN isolator contains 4 isolation transformers, one for each channel in TP ethernet. They are supposedly far better than the simple magnetic ones that usually are in ethernet switches and streamers, something I can confirm based on listening with it in the chain.
I haven’t compared it to other LAN isolators though, but it does work and at a not to outrageous price (€179 EUR).