I am trying to sync an external recording device to Sonar X2P and need to set a bit depth of 16 bits.  However, the bit depth box is grayed out.  Does anyone know why?  I am running a Saffire Pro 40 interface with Asio4All drivers. 
 
Thanks,
MSR
 

In the Unified Preference View, go to File>Audio Data and in the right where is says Record Bit Depth, change that to 16Bit.
 
Then, you will be good to go.

Because ASIO4All is telling SONAR the driver is 16bit. Try the factory supplied ASIO driver for 24bit operation. It may also be a good idea to completely remove the ASIO4All software.

thomasabarnes
In the Unified Preference View, go to File>Audio Data and in the right where is says Record Bit Depth, change that to 16Bit.
 
Then, you will be good to go.

I don't think so. If the driver is fixed at 16bit, changing the Record Bith Depth will not change the driver setting. This is the fix for projects recording at 16bit when the driver is set to a higher bit rate.

I think what I advised will work, scook. If he does what I recommend, that will make the current project set to a 16Bit bit depth. I think that's what he wants. Unless I'm misunderstanding him.
 
If he tries what I say, which doesn't take any time to do, he can come back and say if it worked or not. 
 
But I must agree, it would be better for him to use the ASIO drivers of his audio interface. I don't know why he isn't. But I'm not a Saffire fan, though.
 

Your problem is you are using asio4all...Why, your interface comes with ASIO drivers,,, use them. asio4 all is a very pour driver and only used for on board sound cards.
And also there should be no sync issue. Word clock is sync, bit depth is a how long the data block is. We usually dither when reducing to a shorter bit depth. 

Definitely misread the OP. Forcing the project to 16bit Record Bit Depth may work and is easy to test.

The thing is he say's 

msr
I am trying to sync an external recording device to Sonar X2P 

So to me this implies clock rate, As in transport or word clock. Bit depth is not an issue with syncing gear usually. 

I see what you both mean. 
 
What I got from the OP's post is that he wants to have a SONAR project setup for 16Bit bit depth. If that's what he wanted, I told him how to do that.
 
When I posted that he would be good to go, I mean that's the way to setup a project to have a 16bit bit depth. If he does what I recommended that will make him good to go with a project setup for 16bit bit depth. That's all I meant.

+1 to ditching ASIO4ALL (specifically uninstalling the drivers completely). The ASIO drivers (MixControl software) with the Saffire are what you should be using.
 
Sample rate is then adjusted from the MixControl software. Bit Depth as per post #2 above, but I would default to not changing those and dithering to 16 bit on a mix down (but I am not sure what you are doing so cannot speak to this really, just an opinion).