Sonar has been extremely stable for me for the past few months except for two projects. Last year I was using Izotoph plug ins for the first time and was getting continuous crashes. I worked with izotope support with no solution.
 
At the time I was putting all the plugins in an FX chain to save time. For giggles I instead just called the plug ind up one at a time and the crashing stopped. I just shrugged my shoulders and went on making music.
 
A couple weeks ago I started finishing up a project I had started some time ago. I was almost finished putting in the last instruments when I started getting the crashes again. It would come up saying that "Izotope 5 Dynamics caused a crash" or something similiar to that. I had updated Izotope to 7 when it came out and didn't see any izotope 5 plug ins in any tracks (even the hidden ones).
 
Yesteday I discovered that I had started using the FX chain in Prochannel and they indeed had Izotope 5 plug ins. I removed them and now that project is very stable. 
 
I'm assuming at this time that the root cause of the crashing was putting Izotope  plug ins in an FX chain. Not sure why, but I'm just reporting what I've observed.
 
Anyone elso seen this? My solution is to just use track templates with the plugins not in an FX chain.
 
Walt