Hi everybody. It's happening that every time I "touch" pro chan, audio engine stops. It's not related to asio buffer size because I can use lots of plugins all togheter with any problem; It's not related to the disk cache. Any change to settings doesn't produce any improvement; It's not related to the graphic card. I replaced my GT9400 ge-force with an ATI ddr 2gb but problem is still there; If I "stress" GUI in other ways (opening with dual monitor all the wiews and moving every kind of object, playback doesn't NEVER stop!!! This happens "equally" both on X1 and X2. I can't say when and what has changed my perfect DAW. Yes it was a real killer until the nightmare started. I'm quite completely sure that there is some conflict with any other application or driver but I can't imagine what! CW support didn't give to me any answer to my help call... My PC is built on a AMD phenom quad core with 8GB of RAM on Win7 64 and TC Konnekt 48. Any idea???

Did you check your firewire connection? Reseat the cable. Disconnect the TC Konnekt48 and see if it still happens. 

Thanks. It was my first operation to check what was wrong. It produced any effect. But, as I told, if I don't touch the Pro Channel, even if I upload on tracks lots of "heavy" plugins, the audio doesn't stop! The DAW records and plays perfectly! ???

Thats weird. Are you using a control surface? I'm not sure what you mean by "touch prochannel". Did you mean clicking on the prochannel tab or adding modules?
I would start by resetting your audio configuration to defaults and see if that resolves anything. Under preferences | configuration file. Also try it on a new project by just inserting empty tracks an troubleshoot it one step at a time and eliminate a specific project.
Its probably best for you to call tech support since they can walk you through various steps and identify whats causing it. Troubleshooting over a web forum is not that easy. 

Troubleshooting over a web forum is not that easy.

Tell me about it. We do it all the time here.

But it is interesting that we often have success.

Thank you Noel. Touch means that every time I put my mouse and I click on Eq, or click on the edge or on any control of the modules, the audio engine stops and the dropout indicator appears.
I'm using alpha track remote... I tried without it but with no success.
Of course I have already rolled back the Sonar configuration to factory set but having no result.
I'm writing from Italy and I don't practice English very much so I rather prefer forum where lots of problems find solutions.
I thank you for your answer...
Hope we'll find together something to solve this problem.
 
I just add that latency checker tells me that My pc is aOK under normal mode.

I can duplicate this as well on certain projects. Seems to be more apt to do it with memory intensive plugs added in FX bin, but yes if transport is in motion, any messing with PC will create a dropout.

As Noel suggested, reverse engineer it-Id do a SAVE AS then start removing things 1 at a time until you can narrow it down on the copy project.

piangio: X-2 build 308 is very solid, i dont get any glitches at all ! Im calling up eq's on the fly, moving eq points at random, still no glitches.. I dont use all the features but I dont see issues here so far , maby you should post some system stats and we can go over your system !!

Starting a new project with only one mono track happens the same problem.
It seems to me related to GUI. For example: When I move the mouse over the project to reach a new now-time point, the points of the track elipse are blinking.
I tried a rollback to three firmware ago in my Geforce GT9400 but with no result.
Please note that this behaviuor happens also on X1.

piangio :AMD phenom quad core with 8GB of RAM on Win7 64, whats the make and model of the motherboard ! nvidia drivers ... 306.23 - WHQL Release Date Thu Sep 13, 2012 the new card is ATI ddr 2gb ,, what drivers did you use for that card ?