And I'm not certain but I think this is the type of thing bitflipper would be able to provide actual advice on (as opposed to me who is having a hard time even formulating coherent sentence on the matter).

Hmm... I'm wondering (and you probably metioned this) maybe there are actual power fluctuations to the hub/devices/etc (again dirty stage power). Maybe a UPS/power conditioning device could help.
 
Again... totally pulling this out of my butt (edit: or I subliminally stole StarTek's answer).
 
 
 

hey, thanks again ... that's why I came here to ask :-) lots of great people with helpful ideas :-)
 
Now we need bitflipper
 
bit where art thou?

He's usually hangin' in the Techniques section and actually I think this is a good topic for that sub forum. Maybe falg a Host to move it or repost (although that may qualify as "crossposting" which I guess is technical a no-no... even though I'm guilty of it on occasion).

I wonder if you are plugged into a USB 3 port?  Some interfaces freak if they aren't using USB 2 ports.
 
Also, something else to consider, though this shouldn't do anything but cause drop outs and crackles and such, MANY people have trouble with Sonar audio streaming because of Wi-Fi adapters/drivers really spiking DPC latency.  
 
I don't know that you can get consistent and trouble free operation of a streaming audio application, such as Sonar, when a Wi-Fi adapter or its drivers are enabled in Windows.
 
Lots of folks explicitly either find a physical switch or function key to turn their Wi-Fi adapters off prior to launching Sonar, or they go into Windows Device Manager and disable the Wi-Fi adapter THEN launch Sonar, turning on or enabling the Wi-Fi adapters only AFTER finishing with their Sonar sessions.
 
You can use LatencyMon to check DPC latency spiking caused by Wi-Fi adapter presence in Windows 8.1, and also see if anything else could cause performance troubles with DPC latency.  Download LatencyMon at this link:
 
http://www.resplendence.com/latencymon
 
Again, the Wi-Fi adapter potential for causing performance issues shouldn't (to the best of my knowledge), cause system crashes, just potentially bad audio streaming performance.  I just thought I would mention it because you indicated above that you are using Wi-Fi.
 
Is there any evidence of errors in the Windows Event log?  (Windows Event Viewer can shed light on that).
 
Also, are there any Sonar crashes where a crash log could be sent to Cakewalk for analysis?
 
And, is there any chance you have your Windows Default Audio Device set to point at your audio interface, potentially conflicting with Sonar for ASIO drivers?
 
Lastly, any chance of a Sample Rate mismatch between Sonar and your audio interface?
 
X3e just doesn't crash that regularly for the vast majority of folks, unless some outside influence is involved - meaning local to that system/environment/settings.
 
Maybe you have some issues with 32-bit plugins in a 64-bit Sonar?  Have you checked for this?
Many folks have completely and deliberately moved away from having any 3rd-party 32-bit plugins loaded into a 64-bit Sonar, because of too many flaky failures and weirdness/instability.
 
Bob Bone
 

Thanks, Bob for trying to help :-)
 
Yet this is probably none of the issues you have spoken about ... as Sonar did not crash (it was the audio interface that was receiving something from Sonar that it didn't like and hence decided to reboot) ...
 
It also happened with the tablet PC in airplane mode i.e. all external connections / adapters turned off (blue tooth, WIFI, ...)
 
Sample rate is at 44.1 kHz, no 32 bit plugs installed (there isn't even a single plug-in used as Sonar only plays back 2 - 8 monotracks and sends them unprocessed to different channels of the mixer) ...
 
Anyway, any suggstion that will make me think about something I haven't thought about yet is much appreciated.
 
Thanks, Rob

Bertl: See the firmware is updated on the x32...Please post the make and model of the laptop.

StarTekh
Bertl: See the firmware is updated on the x32...Please post the make and model of the laptop.

Had listed it above ... but here it is again ...


 
Laptop: Acer Tablet ICONIA W700, i5-3337U @ 1.8 GHz w/ SSD drive 4GB RAM WIN8.1 64bit
 
Device Chain: Acer Tablet => USB => X32 rack (@XUSB USB2.0 port) => LAN => S16 Snake
 
all other connections via XLR into S16 snake, except X32 MIDI OUT into LINE6 POD X3 Pro (to change bass sounds along with X32 scene changes)
 
X32 rack is hooked up to WiFi router biuld into rack for remote access with an Android tablet

FreeFlyBertl
- AND EVEN MORE STRANGE: when brought back to the studio, the same setup with the WINDOWS 8 tablet works perfectly in an extensive long time test ...

- EVENTUALLY, we changed to the backup DAW (which is a desktop WIN7 64 bit PC housed completely inside a metal housing, aslo running Sonar X3e) it ALL WORKED AS ALWAYS i.e. the entire show runs without a glitch (no reboots, no problems, ...)

FreeFlyBertl
- AND EVEN MORE STRANGE: when brought back to the studio, the same setup with the WINDOWS 8 tablet works perfectly in an extensive long time test ...

So it looks like the machine.

As a matter of routine I would do the following:

Do a full backup.
* Upgrade to X3E (you are running X3C according to your footer).
* Run windows update several times, get most of the optional updates installed as well.
* Update firmware and drivers of X32 to latest (I know you appear to have ruled this out but would do this anyway).

More importantly...

* Update your motherboard BIOS
* Run Intel driver update, get your chipset updated:
http://www.intel.com/p/en_US/support/detect
 

from what you've posted, i think i'd be looking at the environment differences - power supply, networking etc - any way you can get back to the venue and try and reproduce?