https://bugs.winehq.org/show_bug.cgi?id=50244
--- Comment #3 from Hans Leidekker hans@meelstraat.net --- (In reply to Hans Leidekker from comment #2)
It's redirected and then resent without the data:
0174:trace:winhttp:send_request full request: "POST /cgi-bin/WebObjects/LicenseApp.woa/mc/Melodyne4Service/activateHost?v=1 HTTP/1.1\r\nAccept: application/json\r\nUser-Agent: HTTPProcessor: com.celemony.melodyne\r\nConnection: Keep-Alive\r\nHost: connect-v1.celemony.com\r\nContent-Length: 0\r\n\r\n"
which probably causes the empty response.
With the Content-Length header fixed I still get an empty response.