I would try to separate the debug process. Try using MIDI-OX to debug if MIDI receiving stops after some idle time, without involving Cantabile in the picture. Or you could use MIDI-OX to check if MIDI arrives from the port even when Cantabile is not reacting to it.
I also wonder if your laptop received the windows update that people is talking about here:
New Windows MIDI services - heads up; a breaking bug!
possibly creating some issues.
You could also try to uninstall/reinstalla Yamaha ASIO driver.
The fact that Cantabile hangs and that it is not possible to close it could also point to an hardware issue.
Just my 2 cents,
Gabriel