I have just installed Behringer ASIO XAir driver v4.38 in Windows 10 pro x64. Opening audio settings I found only Line Out 1-2, 3-4, 5-6, 7-8 and the same for Line In (see pictures). What about Line 9-10, ..., 15-16, 17-18? In DAW I see all 18 devices instead.
That is because Windows (and its apps like Skype, etc.) does not recognize the ASIO driver. What you are seeing is probably the WASAPI or WDM (built in) driver which is limited to 4 stereo pairs. The app itself (such as many DAWS like Reaper, etc.) have to be ASIO compatible.
Paul Vannatto, Volunteer Forum Administrator and Moderator
I've looked in the driver in windows settings and it shows the asio driver is there but inactive. Previous driver works and shows asio active in the driver in windows settings. The previous driver works as expected while the new driver does not. Others have downloaded asio4all and it shows all available inputs and outputs. This tells me that somehow there should be a way to activate that driver either by behringer or by the user.
With some DAW's (Sonar Platinum in my case) you have to specify which type of driver is used and IF asio, which asio driver AND then which pairs are active. Installing a driver in itself does not make it THE driver for the app. There is a Preference page where you tell it which type (asio, WDM etc etc) to use and then what settings to use, buffers, sample rate etc and THEN select which driver pairs are active. It is possible if you have more than 1 type of device attached to your pc, to have another devices asio pairs be the active ones even if the new driver is listed. You need to uncheck one device and then check the other within the app. Only one asio device can be timming/playback master. Long story short, the DAW usually determines the driver pairs and type driver it uses.