When I try to record 24/96kHz Sonar-x3e it causes my interface too click back and forth between 48kHz and 96kHz . I have too close the file. And I don’t know what’s causing that I’m using Windows 8.1 and Focusrite Saffine Pro 40 interface. Mix control 3.4
I can record at 24/96kHz in Sound Forge 10 and Pro Tools11 .

If the project was created with a 48 kHz sample rate, or if that is the default rate, SONAR will keep trying to tell the interface to switch its driver to the project sample rate.
 
Try this as a diagnostic. Open SONAR but don't open a project. Choose Edit > Preferences and under default settings for new projects, select 96 kHz. Then close preferences, open a new project, and set the Focusrite interface to 96 kHz.
 
Does this work?

didn't get that far Sonar keep crashing and  I get Audio Hardware failed.

Don't know what else to suggest. I've recorded many projects at 24/96 with a variety of interfaces, but not the Focusrite using Mix Control and not using Windows 8.1 (W7 64-bit). Maybe try the reverse order - using the Focusrite panel to set it to 96 kHz first. Another possibility is to try a non-ASIO driver, like WDM, and see if you can get them on the same page. If so, then switch over to ASIO.

I'm thanking clean install of sonar my do it.
But Thank You

I'd try a clean install of the Focusrite software first. You shouldn't have to do a clean install of SONAR, I suspect it's something misset somewhere. Did you try WDM?

I tried WDM it works. but limits me to two channels.

Any other apps competing with sonar to control the interface?

I use a Saffire 24 and the Focusrite drivers are scripted to allow SONAR to override them... HOWEVER...

1. Ideally MixControl should be opened before SONAR and set to the sampling rate you want.
2. The default for new projects should be set in SONAR (preferences) to the sampling rate you are using.
3. Windows should not be in exclusive mode (sound card properties), and not assigned to a sampling rate you are not using (for me, my Saffire is not set as my default sound output, my HD Realtek is).

I have not used Win 8/8.1, so cannot speak specifically to that; but if there are conflicts to sampling rate, please check Windows preferences, SONAR, and MixControl to ensure they all match. As I do not use my Saffire for Windows, it boils down to MixControl and SONAR.
 
Please also be sure that you power on your Saffire first and adjust the MixControl settings, then open SONAR.
 
 
 
 
 
 

Any other apps competing with sonar to control the interface?
 I don't know  

Ideally MixControl should be opened before SONAR and set to the sampling rate you want 
The sampling rate changes when I open Sonar and before I open a new project 

my Saffire is not set as my default sound output, my HD Realtek is 
yes 
I re installed mix Control no luck.
I'll stick with 24bit 48khz but thank you for all your Help.