Not sure we are talking about the same thing, but sometimes a song will play a few measures and stop.  Nothing but a restart fixes it.

I decided not to dwell to much on the project. I opened up other older projects and had no trouble with them. One of them had 20% more cpu usage than the problem project and it ran fine.
 
Maybe it's just a corrupt file? Sort of a bummer really since it was a really cool track. Either way, I don't think a re-install of Sonar is needed since other projects run fine.
 
thanks for all the feedback!

Just to verify, did you adjust the audio and I/O buffers? I had a very repeatable audio engine dropout with the X3 demo file (exactly at the start of the 18th bar every time) because the buffers were too high. The X3 demo file is actually a good one to tailor your buffers with because it is handy and fairly complex (mute the final mix down track, and play the rest of the file for the test).
 
Tailoring DAW buffers:
Stay in ASIO mode first. There is some tailoring that needs to be done between the audio buffer and the I/O buffers. I had my ASIO buffer too high the other day and FastBikerBoy sent me back a nice PM on this:
 
   Start with the ASIO buffer at 128 (Preferences->Audio->Driver Settings->ASIO Panel...), and I/O buffers at 512 (Advanced Mode: Preferences->Audio->Synch and Caching)

1. Set preferred audio buffer.
2. Start playback.
3. If it drops out or other issues adjust I/O buffers. Try 512 for both as a starting point.
4. Repeat steps 2 & 3. Try adjusting buffers both up and down until happy. 256 jumps should do.
5. If after trying all sizes up to 1024 you still have issues go back to step 1 and increase audio buffer.
6. Repeat as necessary until you find the "magic" combination for your setup.

   The 128 audio and 512 for I/O was the "magic" combo for me.

I'm not sure op is supplying feedback about what he is trying... Fair enough good luck with that.

I stated that I tried the buffers both audio and midi. I've adjusted latency setting. Those are the simple things to try.
 
The event viewer says that Sonarpdr hangs.
 
I noticed last night that there were track oddities. Tracks that won't play for whatever reason. I copied the clips to a new track and they played but there is still more weirdness I'm finding out with this track and have no idea how it got this way.
 
I had to stop messing with it as it was consuming to much time. I'll probably give it a go again tonight.

I asked you a load of other questions in my original post which you still haven't responded to (just two).
 
Here is a checklist...
 
Does this happen with new projects?
Have you updated all your drivers esp your sound interface?
Have you run windows update?
Run this: http://forum.cakewalk.com/Driver-Boost-m2928792.aspx
 
I also asked you if you are running X2A and you said you were running X2 (which was obvious from the start), I then suggested you install X2A and I still haven't had a reply.
And....
 
> The event viewer says that Sonarpdr hangs,
 
Please paste the FULL error message. Right click -> Copy - As Table.
 
Example below.
 
e.g.
 
Log Name:      System
Source:        nvlddmkm
Date:          20/11/2013 23:30:15
Event ID:      14
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:     blagh
Description:
The description for Event ID 14 from source nvlddmkm cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

\Device\Video5
!051d(2558)

Event Xml:
Error    20/11/2013 23:30:15    nvlddmkm    14    None
 
Sorry to be pushy Robert but we need your specific feedback should you need to get to the bottom of this... We tried to help now give us some feedback when you next get a chance.
 
Thanks,
 
Alex
 
p.s.
 
Yup you could try copying and pasting everything to a new project.

Whelp, I have no idea what I did but I just played the track and it worked fine. I'm going to go bang my head on something or maybe count to 10. I haven't decided. I guess the good news is that it's working fine.
 
There were tracks that were not showing up in the inspector properly. Say track 32 was a secondary guitar track. I record both an amped and clean track and in this case, the clean track, 32, was not showing up properly. Every other track would show up in the inspector but that one. When I selected it, or just put in focus, the inspector showed it's bus going to itself.  I copied the clips and put them in a new track, deleted the weird ones, there were several, and set everything the way I wanted. Plus I did some window cleaning and both seemed to have fixed the problem.
 
That "driver booster" was a nightmare. It updated drivers fine but played havoc on the Catalyst Control Center (the software to control my video card). I guess I'll use it to find out what needs updating and just go find the drivers myself rather than let it do it.
 
Thank you everyone for helping.
 
BTW - CakeAlex, Welcome to the forums! ;-)

BTW - CakeAlex, Welcome to the forums! ;-)
 
Yeah sorry I misread your postcount, I've been answering a lot of posts lately ;)
I still think you need to paste the error from the event log, but whatever...