just bought a new wired XKey 37 to connect to a Win 8.1 machine. (Actually two different 8.1 machines). In both cases the install of the XKey Plus after install of the basic XKey OS generated a Windows error message and killed the basic install. No FAQ’s about this. So am using basic install with no additional enhancements possible. Also when Bluetoothing from Win 8.1 machine to speaker, is significant (1/4 second) delay between key strike and sound. Doesn’t happen with hardwired headphones.
Can you share the error message of XKey Plus installation on Windows to us? We did not hear similar problem before.
Regrading the latency between Windows machine and Bluetooth speaker, yes, because Bluetooth audio used another protocol which has high latency than Bluetooth MIDI. So please use hardwired headphone or speaker for professional purpose.