Comment by greenavocado
4 months ago
Speculating here based solely on general networking knowledge. You may have "AP Isolation" enabled and/or multicast blocking on your network may be causing problems.
If I was working on KDE Connect I would add a microphone and speaker based pairing system using OFDM modulation lifted from Rattlegram. Each device would share all IP addresses associated with themselves using sound to broadcast the information.
Just use Bluetooth. These days it's very uncommon for a PC to not have Bluetooth. More of my PCs have Bluetooth than have microphones.
Maybe the Bluetooth connection can be used for IP and port discovery.