About the wifi extender. I believe they work for sure. I know some people that use them as well. But the question is what is the reason they work. I think one does not have to deal with crystal sync, because the signal is clockwise tapping not as strong as a datastream through a cable. Maybe that is the reason people think it's the best solution, but I like to find out why 🙂

This view has changed only recently and all the older theories are now thrown away, as i see it. Try explaining why the Network Accoustic Muon Pro Streaming System seem to solve all problem, more or less. It is just a passive filtering that makes the DAC sing like never before. In my opinion Hans Beekhuyzen has already explained it all here: https://youtu.be/ZCFvIzzMqfk?si=dK6BfzjG-uY-bmh_

About fibers. They do not work better than copper for sure. They do not block more noise than they cause. And the crystal sync even though fiber seems to take place as well. I have a few hundred meters of fiber cable and several converters left from the last session 🙂

No, they work because they are separated from the ethernet connection and therefore is clean from all the noise that is earlier in the ethernet signal chain. It is basically just a fresh start of the ethernet signal chain.

The crystal sync issue i don´t understand. To me, digital works or it doesn´t. The only thing that can influence the sound is if the analogue conversion is not able to do its job perfectly, which happens if there is noise degrading that process. The digital part is always perfect and can´t influence the sound. That is in my mind impossible.