Hello! I have this same issue. We first noticed on our build server. We tried to do the same from a local Macbook of several developer. No luck with the vpn connected. When it disconnect the vpn, the upload works fine. This happens with all (four) tested developer machines. With vpn on: fails with the above handshake error. With vpn disconnected: works on any of the Macbooks tested. Did anyone find a solution for this yet? Thanks! Frans

Yes, I have the same (currently on my M4 Pro, previously on my M1 Pro). Specifically noticeable if you are running music in the background while working in Xcode. The 'solution' I have is to kill the audio daemon. It will then auto-restart and it's ok for at least a while. Use: 'sudo killall coreaudiod'.