HA!  The ultimate in easy fixes. Re-booted Sonar.  When in doubt...
 
YIKES!  I didn't need to normalize a clip until today, about a week into using X3.  As I've done for years, selected the clip, found Normalize in the Process menu, set it to -1 as is my habit, since full 100% can get ugly.  But talk about ugly!  The clip emerged a solid brick of peaked out noise! -- Tried again on the same clip, on other clips - sound was totally destroyed every time.
 
This is a known issue, or am I being weird again with my X3 questions?
 
Randy

Works OK for me.   I use it pretty regularly.  Possibly your track just does not have any dynamic range?
 
Glen

Working relatively fine on my end, and I've been using it quite a bit the last couple of weeks. Occasionally, it will not recognize that a peak wasn't slip-edited and do nothing (or make the clip softer) thus making me undo and bounce to clip, but no problems with distorting when increasing the gain.

Not every audio is going to do well with normalize. One reason is the answer above. Also too much dynamics can also not work well. 

I just did about 70 normalization/gain change operations on mono vocal tracks over the weekend without anything unexpected.
 
What happens if you trim the clip first prior to normalizing?

It now says "solved." What solved it?

Thank you all for super fast replies - It was one of those mysterious temporary glitches.  It was making solid peaked out bricks - beyond space distortion.  I closed the project, closed Sonar - Opened again, Normalize worked fine and as expected again.  If every issue could be solved so easily!  I should have tried a re-boot before running to the Forum. 
 
Randy

First line of defense with mystery issues: close project and re-open.
Second line of defense: close Sonar and re-open.
Third line of defense: re-boot Windows.
Fourth line of defense: Go to the forums, and hope scook, brundlefly, bitflipper, etc. is online.

Anderton
First line of defense with mystery issues: close project and re-open.
Second line of defense: close Sonar and re-open.
Third line of defense: re-boot Windows.
Fourth line of defense: Go to the forums, and hope scook, brundlefly, bitflipper, etc. is online.

Absolutely, Mr. A.  As I said, I should have re-booted Sonar first before posting.  I'll tryyyyy to be better, I promise. 
 
Randy

Hey, we're all in this together. People will read your post and go "hmmm, maybe i should try re-booting Sonar to solve my current mystery problem" and you will have saved them so grief.
 
Remember, the people who don't have problems usually aren't here. They're off making music.