SONAR X3d PRO : VERY STRANGE AND ANNOYING PROBLEM WITH ONE PROJECT !? HELP PLEASE !

Hello to everybody
 
Just a few words about my config :
Sonar Producer X3d
VS 700 Console and soundcard
Windows 7 64 bits, i7 970, 12 Gb ram
 
Few days ago, I opened a new project in order to demo the SOUNDTOYS Native effects bundle. The project results to be not heavy, with about 20 tracks (wav recordings, rex loops ...) and about 5 auxiliary sends, testing various combinations... This was OK at the beginning, but, gradually, when I had to reopen this project, it was very slow to start. Once opened, there was a lot of audio engine drop outs but that worked; when I closed it, there was the message saying that Sonar has stopped to work... And finally, when this project opens, whereas all my routing configuration is correct, I have no playback sound (either without sound indicators in the Vu meter of the tracks and busses as if the tracks were empty, or with signals).Now, THE WORSE  is once the project is closed, my system is disturbed and when I open any sonar X3 project, I have the following message :
 
There are no audio devices for your current driver model on your system. Please go to options/audio and choose a different driver model. But I have absolutely no option to select anything. when I click on drivers there are none to select. 
So I have to restart the VS 700 console and soundcard, but some times, the resut is the same and I have to restart  the computer and the VS700 : very annoying ! (NO problem with the other projects !)
 
Would you have any idea ? Maybe I suspect the Soundtoys plug-ins as they are a little bit cpu consuming in comparison with other plugins, but my processor had leeway. What I don't understand is that at the beginning, things were OK, and it gradually worsens; there were essentially Soundtoys , Waves and Lexicon plugins but I'm very careful and when I don't use a track with plugins inserted, I deactivate them ! Maybe I tell nonsense but the delay calculation for the Soundtoys delay plugins has generated some disturbance in Sonar (??) But the fact that this project causes lost of my audio drivers gives me cause for concern because If it was a serious project, I would lost all my datas !
 
THANK you very much for your attention and will apreciate all your advices !
 
Pierre

Thanks a lot brundlefly !
I 'm not very acquainted concerning computer specifications, but it is surprising that only about 20 audio tracks (no Virtual synth...)  push my ram to the limit, with only some plugins. I had "heavier"projects and it was ok (??). Anyway, I will take a look at what you mentioned. Thanks again

There are no audio devices for your current driver model on your system. Please go to options/audio and choose a different driver model. But I have absolutely no option to select anything. when I click on drivers there are none to select.
So I have to restart the VS 700 console and soundcard, but some times, the resut is the same and I have to restart the computer and the VS700 : very annoying ! (NO problem with the other projects !)

do you have your internal sound card disabled? I would disable it and make sure Sonar doesnt see it. This can cause what you are seeing.
 

Once opened, there was a lot of audio engine drop outs but that worked; when I closed it, there was the message saying that Sonar has stopped to work...

The new FX you inserted and are demoing may need more CPU, so you will need to raise your ASIO buffers or WDM slider. Some plugins FX need more resources than others and depending on your sound card driver settings, you may need to adjust it.
 
CJ

Thanks very much for your help, highly appreciated !!
Cjays, thanks for the advices, but everything was ok (internal sound card disabled).
Phonic, maybe a reinstall could be the solution, but I don't explain why this is this particular project which is failing (??). 
Brundlefly spoke about the memory in the task manager, but I don't know if the numbers I noticed show something wrong ?

The Task Manager numbers are fine (37% CPU and 2.8GB RAM) so long as that RAM number isn't continually increasing or approaching the limit of what's available.

Thanks Bob for your settings recommendation but I have the same settings, and until then, no major problem ! (Except sometimes some incidental and intermittent freeze and crashes and in particular, with the Plug-in PSP master comp (inserted in a mono track) which made inevitably crash Sonar X2. just a week ago, I upgaded to X3). Concerning recording, I always record "dry" without effect...
Concerning the incriminated project, this just around 20 tracks of pre-recorded wave clips and some loops; no virtual instruments, and when I mute a track, I always deactivate the effect...
 
Thanks brundlefly for the confirmation !
 
Bitflipper, thanks very much for the advice, but I've already checked the Windows' Sound and Audio Devices control panel applet, and it seems everything is in order.
What it is odd is that the disorder is just caused by this project (which have Soundtoys and Waves plugins, but maybe, it's got nothing to do with the problem) and it's always the same scheme : once this project closed, I have the message : Sonar stopped to work, and after, every project I open, The audio driver are missing. But I haven't checked if at this precise moment, the audio devices and drivers are present in the Windows panel (?). In any case, when I reboot my system, everything is OK, except until I open this particular project.
I should uninstall and reinstall the drivers but I intuited that there is something else, because, in my humble opinion, the other projects would have similar problems.

Hey Bob,
Yes exactly, I'm trying another project with the Soundtoys plugs (Microshift, Decapitator, and Echoboy) : Until now, everything is ok. I noticed these plugs are "heavier" than the average, all the same and there are some slowness and strangeness concerning GUI display. I just remember that in the "mad" project, I made quick test by changing the original tempo (I passed from 95 bpm to 132 and vice versa) in order to test the tempo synchro of the delay based effects of the Soundtoys on some loops; maybe there is nothing to do with the problem...
 

Hi Bob,
Thank you very much again for your very appreciated kindness in order to help me !
I've just downloaded the demo version of these plugins few days ago and all the Soundtoys plugs are  in version 4.2 with 64-bit support for Audio Units and Windows VST formats, since August 5, 2013. I'm very careful to work only with 64 bits plugins.
Yesterday, I reported the problem at Cakewalk and Soundtoys, and waiting for their feedback. But I suspect that if I'm alone to have this kind of problem, I'm not sure that they go further...
Thanks again