it's less problematic to stay at least one generation behind with respect to your OS and software pairing.
I would normally agree with this, but it was do or die time for Microsoft with Windows 10 after the Windows 8 fiasco, so I was confident it would be a good launch, and it has been.
I did wait a few months after the release to upgrade - this has been the first and only problem to hit, and I play around with Traktor 2.9, Mixvibes Cross 3.3.11, a little known thing called Digijay, and obviously Mixxx. All the newest releases, all 64 bit, all running solid. 10 works real good, and my laptops are no great shakes.
I have other sound cards, so for me this really wasn't a problem, but I did want to get the DJIO to work with Mixxx. I did, and I was just getting ready to post it -
The issue is specific to Audacity, Mixxx, and other "open source" software that use PortAudio, a cross-platform audio I/O. Seems it doesn't play well with Windows 10, especially if the ASIO driver for your soundcard isn't really "compliant", whatever that is. The temporary "fix" for the Numark DJIO is, before you open Mixxx, go into Windows "Device Manager", select "Sound, video, and games controllers" and then disable "Numark USB Audio - WDM 2.9.64". Now when you open Mixxx, all the Sound API's (including ASIO) are available, and it works fine.
Obviously, you shouldn't have to do this - I have notified Numark and suggested that they let Ploytec GmbH (the driver developer) know.