Constant crashes , recent full scale upgrade/purchase, not happy.

Even if you're seriously considering jumping ship, and I don't blame you for the cursidents you're experiencing, but it may just be a whole lot less trouble to contact both Focusrite and Cakewalk support, if for no other reason than to let them know about the issue. It could help the rest of us avoid such an issue in the future.
 
Now, from my perspective, if you've seen the latest evolution in Mac Pro's, you'll see Apple seems to have no interest in DAW's any longer. I'd be very wary about jumping into a Mac, if it were me. If you already own a fast Mac Pro, for example, then the investment's already made for now. Just know the future Mac Pro's don't have PCI-e slots.

Ryan Munnis [Cakewalk]
Are you sure it's not your device driver crashing SONAR?

What two audio applications do you have open at the same time? Are the stand-alone applications or is one set to slave to the other via ReWire or something similar?

If it's not set up via rewire, keep in mind doing this is forcing them both to access the audio driver for your hardware simultaneously. It's not impossible, but it's not always the best idea depending on the nature of the programs. Some drivers behave much nicer with this than others. SONAR has an option to share drivers with other programs, and for the most part it works pretty well, but some drivers don't necessarily appreciate that. This might be the direct correlation between dropouts and crashes. I can't say for sure without collecting specific information though.

Give our support team a ring when you can. They can help to identify the root cause of the crash by collecting some info from your system.

 
thanks for the reply, I will do that....I do have the 'share drivers' option ticked....I was so hopeful that after years of NOT getting my Echo Layla 3g to share with anything else, the Forte would do it...

Matt that is awesome support you are providing. Hats off.

I think it is pretty established that having Sonar and a stand-alone audio application open at the same time will crash ASIO.  For example, I can't have Sonar and stand-alone Kontakt open at the same time.  Doing so will kill the audio and require a restart.  Whether or not it should be this way, that's how it is.
 
In my case, I often have crashes or lose my audio engine if I open two Sonar projects at the same time, but this should not happen.  I don't think this is true or should be true for most people.  For me, a normal project and a very small MIDI project are OK, but two projects with a lot of soft synths or audio tracks will crash me.

In my opinion, It isn't a Sonar problem, nor a Focusrite problem. It is just getting everything to gel properly. I am running X2 on XP without any problems. I am 1.87 Ghz, and way under standards. My lead player also has Sonar X2 and Focusrite, using an older laptop. Be patient, and go over all the stuff required. I realize you are not new at this, but I also had crashes constantly when I first installed X2. I finally got it all corrected. It can be many issues causing problems. But I feel certain a little patients will go a long way. All DAW's will have some issues reguardless if it is Mac or not. As the technology is created for us to constantly have to upgrade etc...It is more about making everything you are trying to work with communicate without such things as graphics drivers and multiple sound cards not communicating properly.
 
Use ASIO drivers. Once I switched the drivers, and then switched back to ASIO and it cleared up some issues. Set up to 44,100 x 24 bit render and record. Set advanced tab in preferences, and make sure you are useing all your cpu. Set Configuration File / Thread Scheduling Module at 4, if you are using a quad core. You should show 4 bars in the performance pane when done correctly. Disable the motherboard sound card, and turn off Windows sounds. Make sure the other DAW's or soundcard are all gelling at the same 44,100, 24 bit. If you swap to another DAW, you can temporarely turn off the Sonar sound engine, and see if that stops the crashing. Set you Devices at proper inputs 1-8? and the outputs at 9-10? or whatever jives. Driver setting playback master at main outs 9-10? Record master to 1-2. I select always open all devices, but I do not share drivers. I have 3 sound cards, and I am not getting crashes. I use one for midi, and another for recording at my interface, and I use my interface main outs. My interface is an Aradvark Q10 and it is 13 years old. No drop outs and no crashes. Set your buffer to allow for a latency of about 10-12 mills. Maybe a little less with newer gear. If you have files with plug ins and mixed trakcs such as 48000 and 44100, avoid them until you get the crashing resolved as they cause me headaches. Just set it all to 44,100 x 24 bit. However you can render at 32 or 64 if you prefer.
 
When you create a send, do it in the mixer console view, and send it to a prefered bus. try adding some plug ins at the bus station rather than having multiple ones at the track itself. If you have 5 guitar tracks place them in a track folder, same with keys or drum tracks. Make sure if you are not meaning to use pro-channel, that you don't have it turned on at all the tracks where it is not being used.
 
Stupid things like graphics cards can cause issues. Graphics take presidence over everything on a PC, to show the escreen. Go over your graphic drivers and settings. Make sure it is working properly. Get rid of stuff like game controllers you are not using etc...Here is a site for "windows start ups"  http://www.sysinfo.org/startuplist.php  , you can alo look up Viper I believe it is for a total list on services running  http://www.blackviper.com/  Viper can also show you how to utilize and set up your windows, as to what has to run and what you might not need, search his toolbars at his site. Go over all this and get your PC in good order. Do a virus scan in "Safe Mode". safe mode will pick up stuff it will not unless you are in safe mode. I say this because you mentioned you always had crashes. If you can't get in safe mode, rut ro, you probably have a virus.
 
When you work for hours on a prioject, save it, and close and re-open Sonar to clear it up. this is a good practice. I keep all my stuff on an external and free up my Cakewalk project folder. You can uninstall and reinstall your sound cards if needed. all this kind of stuff will get you on the right track. It can be some simple thing you over looked especially as you say you have always had issues. I used Sonar 4 for several years, and Sonar 7 for several years with no issues. When I installed X2 I crashed 50 times, but I got it all sorted out. It most likely isn't Sonar, or Focusrite, it is most probably just some corruption or settings not properly set, or set properly but not be recognized as such. Little things like me setting to WDM drivers then back to ASIO fixed some things for me. Good luck, hang in there!  Free