Thanks for the input jpetersen!  I have been using Adobe Premiere Pro, Camtasia 9, Melodyne Studio,  and haven't had any probs.  (see my above post).  Sibelius has been quirky though (it won't rewire with Sonar), and it runs ASIO, so, maybe related.  Though it seems others have had Sibelius and Sonar rewire issues too,  so maybe unrelated.
Thanks again!!
Bob E
 
 

Same issues.  I created a file this evening.  2 tracks only.  Both recorded fine.  I edited one clip, using keyboard shortcut S to 'cut' the clip once.  I then 'normalized' one of the 2 clips.  Then I bounced the 2 clips together as one again.
 When I play the file back,  I get a dropout/audio engine error, slightly before the spot where I originally cut the file.
 
If I place the play-head anywhere in the middle of the clip, the file will not play at all.  HOWEVER,  If I move the clip downstream,
my file will play all the way up until 'just before' this clip.  If I re-save the file, (only save, not close) I get the same issue.
However, If I close the file and reopen it, the clip plays fine. WTH?
UPDATED:  Here's a video of this.  2:45 seconds of pure entertainment.  https://youtu.be/PgIigvvLjx4
I am trying to stay positive, and if there is something to take out of this, it's that my skills using Camtasia 9 video, audio and desktop capturing software is getting good.
It's 6am,  up all night.  Can't get over this. WTF.    Please tell me I don't have to jump to ProTools.  Aarrgg
 
I am going to download the trial version of Reaper, as suggested, to see if there's any issues.  I have been using other software, as mentioned earlier, but, what the hell. 
Damn, this is the @!@$% most frustrating issue I've ever had with any software.  As far as HD failures, I have tried two different HDs, as mentioned earlier. (pointing all my folder locations within Sonar there)  Both  drives are internal, both working great for everything else. (SSD and a 7200rpm) 
 
Video editing (sound and video) with Adobe PremierePro, no problems; using a webcam (Logitech C920) to record video and audio, no problems; Camtasia video and audio, no  problems  ect..
Would love to record and create music.
 
Bob E
UPDATE:    I downloaded, installed, recorded, used the same plugins, added effects, cut, pasted, swapped, deleted, undo, redo,etc... in REAPER and had no issues at all.  Same Sample rate, bit rate..... no issues.
 

Wow these are indeed surprising and not typical.  Sorry you are running into these issues.
 
We'll audit the record path to be sure any error conditions that might result in no clip pop an alert so one can know what's going wrong.  A silent fail isn't helpful. 
 
As far as this latest issue, it appears a dropout is occurring for some reason at that particular segment of audio.  Can you send us a bundle file of that project so we can check it out?
 
I'll also contact you privately with some more details.
 
Keith
 
 

Hi Keith, thanks.   I will be working though the evening, but first thing in the morning I will create the bundle file and respond to your PM message about your other suggestions.
Thank you!
Bob E

Here is a clip that may have more insight into this problem.  The audio clip isn't in sync with the waveform picture, and there's some weird jibberish at the end of the drawings, however, there is no sound there.  Sorry for the vids, but each time I have an issue, I want to document it, so I can explain and demonstrate the issue. 
I have fast hard drives, and I have also tried moving my picture cache folder to a separate drive.  And cleared it out.
 
Is Sonar having issues with the video rendering, or graphics card?   I have an NVidia Geforce GTX 970 and no problems with it.  (I don't play games with this computer)
Any ideas?   Getting desperate here, and waiting, and waiting for a response from tech support.
Maybe this vid, (or the others I posted earlier) can shed some light??
https://youtu.be/JRUVNg18ekY
 
Thanks,
Bob E

If anyone needs to see my settings in Preferences,  I did a quick screen capture of all the tabs and windows there.  If that helps.  
'quick demo of all my settings
https://youtu.be/dKlfS1iZJy0
 
one more vanishing clip strange video
https://youtu.be/7A9H_UZnzVw
 
Not sure what to do now.  
Thanks,
Bob E
 

This looks strange to me:
 

 
"M:\_myCakwalk Groove Clips plus" is your WAV file location ?!!!??
 
EDIT: OK, I realize that per-project audio folders probably make this redundant... but still, it stands out to me as something abnormal.

Here's something that might give us a clue.  In a newer file I created, from a new template (totally dumbed down as to eliminate other variables)
I began having problems.  It's always after preforming some kind of edit, drag/drop or bounce to clip.  I can record a track(s) until the cows come home, with no problems.
It's after doing any edits that all these issues happen.
 
I opened the 'project audio folder' within the sonar browser.  Among the expected wav files, there are 3 wav files that are 4kb in size.  When I play the file, they pop up in the browser, and when I stop playback, the files 'disappear' from the browser window.  (except one I think)
 
These 3 wave files are empty of data.  (when I play them in windows, the error message says this.  However, they are in my projects audio folder)
 
I also get an error message if I right-click on the file within the sonar browser that says, (this file is in use by another process, (or something like that) Maybe the file itself? The other process is maybe the Sonar browser/previewer itself?  These files can't be found on the timeline.
Maybe the ‘preview’ engine is causing some issues?   Maybe there’s something going on with take lanes?  I didn’t use them, intentionally anyway in this project.
 
Here is a new video that demos this happening, if you care to see. 
https://www.dropbox.com/s...20wav%20files.mp4?dl=0
 
Hope this helps narrow things down. 
Thanks,
Bob E
 

Hey Bob I've been watching your videos and things sure do seem screwed up. I guess the good news is that Keith is across it. Hang in there man!

Thank you Millzy!