On Windows, there is a new MIDI-API support available, called WinRT MIDI. You can activate it in Studio Setup... → MIDI Port Setup → Use Device 'WinRT MIDI'. If activated, the old MIDI-API support will be deactivated (Use System Timestamp for 'Windows MIDI' Inputs & Use Device 'Direct Music').

Benefits of WinRT MIDI

• Native support of Bluetooth MIDI on Windows
• Better Plug & Play
• Better handling of connected identical devices

Drawbacks of WinRT MIDI

• Old MIDI hardware can run into compatibility issue because the MIDI ports are simply named "MIDI". This is an issue that hasn't been addressed in Windows, however, some components (e.g. some MIDI Remote implementations) rely on specific MIDI port names and they might stop working if WinRT MIDI is used. It is possible though to rename the MIDI ports in the Studio Setup allowing you to identify your ports at least.
• If ports are detected twice, you can uncheck "Use Device 'WinRT MIDI'" and enable it again. The duplicate entries should be gone then.

Bluetooth MIDI may introduce some additional issues depending on the setup:

• If timing is degraded via Bluetooth, try "Use System Timestamp for 'Windows MIDI' Inputs". 
• Plug & Play with Bluetooth MIDI can result in a hang.
  Workaround: uncheck "Use Device 'WinRT MIDI'", connect or disconnect the Bluetooth MIDI Device, then check "Use Device 'WinRT MIDI'" again. 
• Starting Cubase with Bluetooth enabled while the system is linked to Bluetooth MIDI devices that are turned off, a hang on start can happen if WinRT is activated.
• Sometimes there are hanging notes. This may be related to a poor Bluetooth connection.
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