I'm having difficulty changing from the driver mode WASAPI to ASIO. I've been using WASAPI. When I open X3 I get the notice " There are no audio devices for the current driver model on your system. That's because I tried to change to ASIO in the Edit/Pref/Audio/Playback/Recording section. I'm using the interface Roland UA-25. When I open X3 and go to Preferences, in the Audio/Devices window both the input/output driver section is blank. In Driver settings the recording/playback timing masters are empty. In playback/recording I've changed the driver mode to ASIO and underneath it dithering (?) reads rectangular. My computers setting of windows audio devices, the input/output default is the UA-25. I'm using Windows 8.1 and computer less than a year old. Any suggestions on how get the ASIO driver mode working with the UA-25? It's presently just silent with any playback in X3. I can hear any regular audio with the UA-25.

Have you installed the proper driver for you operating system?  It seems to me that SONAR cannot identify your UA-25, although Windows can see it.  It is my understanding that Roland interfaces work well under WDM drivers.  Here is the link for your device's drivers:  http://www.rolandus.com/products/details/704/downloads/
If it is that your driver is a mismatch, I strongly recommend installing the Win 8.1 driver as Administrator.
 
Kind Regards,
 
Living Room Rocker

First, did you try to make sure the USB connection to the computer is connected tightly, restart the PC, and open SONAR to see if the ASIO device is listed in Preferences after doing these things?
 
If the ASIO driver is not listed still, maybe you're experiencing a problem another user shared recently. He was having the same symtoms as you with the ASIO driver not showing in SONAR, but the unit was working as the Windows default playback device. It turned out to be that he recently made a Windows Update and one of the Windows Updates "critical security" updates caused the problem. When he restored his computer to a time before he made the recent Windows Update, his ASIO driver was showing in SONAR, again.
 
If you recently did a Windows Update, you can check to see if this is the problem.
 
Hope this helps.

If it is a USB connected interface, some of them freak out a bit if plugged into a USB 3 port, so that might be worth taking a look at.
 
When changing from WDM to ASIO or the other way around, I dimly recall having to remove the checks for whatever was enabled, then click Apply, THEN I would go change the Driver Mode to ASIO (or WDM, depending on which way I was going), and again click Apply, and then I would see my audio interface show up as able to be enabled as a device.
 
Have you looked at the above on your system? Basically, for me, I needed to take away the current devices, to be able to then alter the driver mode, prior to being able to then select the audio interface as a valid device for the selected new driver mode.
 
I hope that makes some sense.  If not, please post back, and I will take another stab at it.  It seems to be stupidly early here.  :)
 
Bob Bone
 

Thanks for everyone's help. I uninstalled the UA-25 driver and re-installed (after 3 attempts for some reason) but now it's working. The driver I had installed was the latest one but I saw that it was installed in Jan 2014. Probably because of some updates when I was not using Sonar in the last few months somehow messed things up. The re-install did it and things are ok ... for now ...lol. Thanks again to the forum...

Glad it was as simple as that. I was just reading your other thread and was worried this was still not working. And Beagles issue with the Windows updates makes things even scarier.. 
That's why so many here will always advice checking your drivers are up to date as the very first step in trouble shooting. Drivers might be released with bugs and the manufactures will update them a few times before the dust settles. My self I check the Focusrite web site every few months. 

Thanks JohnnyV, & everyone else with helping solve this issue. Never ending learning curve but I enjoy it, frustrating as it can get at times ...

JohnnyV
 
You are correct. In this case, a user should mention to try re-installing drivers before taking more time consuming trouble-shooting steps in an attempt to resolve an issue.