Interesting observation - When I switch in SONAR from a 48k project to 44.1k project, I don't have to change the sample rate in Windows. Seems I have to do it only when going from 44.1k to 48k sample rate. So, if I keep the Windows sample rate on 48k, I guess I don't have to change anything, that is assuming I don't have to change the Windows sample rate for playing audio files outside SONAR that are 44.1k.

I am out of ideas.  I need a screen shot to see what the dialog looks like when you change the settings in Windows, because I have no way of doing that with either of my interfaces (I can change my on board sound settings but I haven't disabled my on board sound cards.)
 
I also have never seen anybody refer to changing settings in Windows unless they are using an on board sound card, which you aren't using. 
 
If your interface and Sonar match, it shouldn't matter what's in Windows which is why I am interested in the screen shot.

I don't know how to attach an image.  All I can find is an option to post a URL.  When I try to attach an image I get a blank box that says "Select from an option below:", but there are no options displayed.
 
I don't know what's so hard to understand. On your Playback tab you must have devices displayed for your onboard sound card. I have the same thing except it's for my Focusrite sound card. Anyway, thank you for trying.

You can upload images to imgur (use the forum option in the share meun on imgur) which is what a lot of people use.  I am not sure what playback tab you are referring to.
 
This is the speaker icon I have:
 
Note that it is set to 48K.  However, I am running my interface and sonar at 44.1K.  Note that this is my on board sound which I am not using.  I have no way to alter my BR800 setting from windows.  I only do that throught ASIO panel and in Sonar.
 
 

From post 9:  one right-clicks on the speaker icon in the Windows task bar and selects "Playback devices" for example. If you then select the device for your sound card, click Properties and then the Advanced tab, that's where one changes Windows 10 sample rates.
 
If you don't understand that then I guess you're not familiar with Windows.  This is not an installed GUI. It's part of every Windows OS.

I see what you are talking about now.  I was not aware of it, because I have never had to use it.  Here is a picture of it:

As you can see, there are no sample rate or bit depth settings to adjust.  My other interface, which is on a Win7 system has the same thing.  I don't know if focusrite is different.
 
Most people only adjust their settings in Sonar and their interface's console.  You should probably leave it at 48K if it works and modify the settings in the focusrite console.
 
Actually, I do see where you can adjust the sample rate and bit depth in the IN properties.  Mine are set to 44.1K 16 bit, but Sonar has 44.1K and 24 bit and I have no issues.   Again I *never* have to go in there to do anything in that menu.