Hello All,
 I have been having some issues with Sonar Platinum and huge audio dropouts. Basically I am half way through recording an album, all was absolutely fine until (this is the only thing that I can think of) I dragged in a vocal guide track from another version of the song on my hard drive through the Media Browser. As soon as I did this the project would then play for a few seconds, then stop, hang for a while and after say 20 seconds the audio dropout box would pop up. It would then take another 20 seconds before I could press play again. I tried shutting down the computer and it still did the same thing. I then tried opening a couple of other projects and the exact same thing happened, unable to play anything without dropouts.  I then tried un/reinstalling Sonar and this did not work, so then I tried creating new projects and copied all of the audio files in, then un/reinstalled Sonar and everything worked perfectly.Until yesterday......
 Yesterday, I again had to drag some audio from another project, this time I didn't use the Sonar browser, but Windows Explorer (I was dragging from a USB stick as the file was on my mixing studio computer) and blammo, exactly the same thing again. Now all my projects will not play and so it looks like I will have to create new project files again, copy in all the audio files (which is now even more as I have started recording all the guitar parts). 
 
Has anyone else experienced this or does anyone have any ideas on what I can do to fix this? I am running Sonar Platinum on an i7 machine with 16gb of RAM. I am using an Allen and Heath Zed R16 desk, all drivers are upto date and up until this problem I could easily run 50 or more tracks with effects, Pro Channel and everything else running and the CPU meters would only be hitting 40% or less. These songs I am working on now are only audio(a couple of the songs only have 12 tracks running, no effects, no Pro Channel and the CPU meter barely even registers.  
 
Any help or possible fixes would be greatly appreciated

Not sure why you would need to create new project files. Even assuming you aren't auto saving and therefore cannot roll back, you should be able to open the project with your sound card disconnected (you will get a message about having no audio device) and then delete the track with the imported audio.  Then save, close Sonar, reconnect your audio device and open the project. Your specs seem fine. Have you tried creating a blank project and then importing the audio or tried creating a track and using import audio from the right click menu?
I usually use the right click rather than drag and drop.
 
It may eliminate possible causes

I have to create new files as this is the only way that I can get any projects to play. What I think is happening is that for some reason whenever I drag in an older audio file it is bringing some corruption with it. So then any project that I open gets corrupted too. The only way I seem to be able to avoid this is, drag the audio in, save, close the project. Then open new project, drag in all the audio files. Save, close. Uninstall Sonar, I also uninstalled the Command Centre. Shutdown, restarted the PC reinstalled everything and all was ok. 
 Is there any data that can be carried across with an audio file recorded in Sonar that can cause this sort of corruption, I am thinking along the lines of time stamps etc that could be confusion? What I have also noticed is when this "corruption" does happen the time line seems to act strangely, the most noticeable thing is that it displays on top of the play/stop button at the top of the project view obscuring it.

uninstalling everything seems a bit drastic to me, if the files are broadcast wav files they may have time stamps but there is a setting which allows you not to import these timestamps.
What format are the files you are trying to add?
What happens if you use the right click handler (add audio track, right click inside track and choose import audio and browse to the file you wish to import)?
I import audio files all the time with no issue

Did your original guide tracks have any Melodyne or V-Vocal edits?
Did they contain any Audiosnap data?
Are they single, contiguous tracks or made up of shorter clips?

Hello Bristol_Jonesey, no they didn't have any Melodyne, Audiosnap, V-Vocal or even comping. The first time this happened it was just a guide vocal track taken from a demo version of one of our songs and then yesterday when it happened again it was a guitar track taken from another demo song. To add to the confusion this latest guitar track was recorded on our studio computer, then I bundled, transferred to our mixing computer (we have 2 studios, one recording,one for mixing) to mix the demo. This project played fine, I then copied the guitar part onto a USB stick, back onto our studio computer and then the audio dropouts started again.

The word "Bundle" sticks out like a sore thumb.
 
What happens if you just copy the .cwp file (plus audio)?

I only bundled the second time this happened and this was to transfer to another computer where it played perfectly. I then just put the audio file onto a stick and moved back to the other computer. 
 The first time this happened the file did not leave the computer. This happened 4 weeks ago and had not been a problem for 18 months or so before this event. (I had always been able to move audio between projects without any hitches) but I cannot think what has changed. 

The other point is I am not sure why this would then affect every project on my computer, dragging one file into one project shouldn't then affect every other project unless something is being changed in the global settings when this happens.
 
 
 

I'm also experiencing tons of audio dropouts - using the latest and greatest Manchester update.  I wish I knew how to go back to a previous load.