on my lenovo laptop, with internal sound card, and with external creative usb x fi  sound card 5.1, i am able to open 24 bit session, import, etc....Sonar for some reason, is locked to 16 bit? is this correct?

In preferences check out record bit depth, render bit depth and import bit depth under File / Audio Data. Also check the Audio driver Bit Depth under Audio / Device Settings. 

Cakewalk does not write interface drivers. You can manually run the Wave Profiler on the Prefences > Audio > Driver Settings screen and see what SONAR detects when testing the drivers.

OK, let me explain!
 
I recorder tracks 16 bit, 48k in my main PC...transfer that to flash drive, an into my laptop- lenovo 4 core...not to record, but to do minor adjustmens...
 
as a test I install trials , studio one, and samplitude, and import a single file to see sound and reaction...!!!
 
 
both, sonar and studio one, for some reason, lock bit to 16, on both internal realtech HD, and creative x fi usb...i know that a x fi, is a 24 bit card......i wdm drivers, and asio4all....with wdm works.....
 
samplitube, converted to 24 bit, and it works with both cards...
 
i do not need infohow to change in preferences. my Q is, how come, samlpitude can playBACK, AND WORKS 24 bit, sonar do not, and s well studio one?  with studio one, you can not even changeone parameter?
 
so, how the sampitude can do this?  the differenece in sound is like day and night.....

not locked here. im using 24 bit / 48 on all projects and dropping them on my laptop for mobile unit.
Try looking at your soundcards preferences. something maybe be locking it to 16 bit / a default in most soundcard.

Check your ASIO4ALL settings to see if it is forcing to 16 bit mode.
 
Glen

just googled, it looks, I m not the only one with this problem..it could be a win 10 glitch, a software that is holding to a driver, , perhaps, samplitube has lock into the 24 bit, and not let it go......or perhaps a video player....strange! is there a wdm driver reset utility?

Try the WASAPI exclusive driver. It blows away ASIO4all now that Sonar has made it work with W10. 
It even works great for me on W7 64 bit. All my stuff is 24bit. 

wasapi wave profiler shows only 16 bit ...or win 10 is blocking, or I do not know what? it is strange, that samplitube works, in all modes inclidong 24 bit,, wdm, asio..but sonar, and studio one is locked to 16.
 
we are talking a process of elimination..if win10 how is blocking,  how smplitudeis working...btw, i do not know other daw exept sonar, this was only for test....same drums file, in three daw, and one stereo track..simple..
 
the diference in sound is that is comeing out is drastic...somtething is interfering, somehow?

Sorry - but I don't believe that a 16 bit wave file imported to Samplitude at 24 bits sounds better at all. It's louder, or you have a different pan setting, or maybe a plug is affecting something. What you describe is not possible, IMO. What do you think Samplitude is adding to convert 16 bits to 24 besides 0's?