I am going to rollback each SPLAT update and see if this issue goes away for SPLAT. X3 does not exhibit this issue. Surely something happened between products to cause this irritation.

Rollback to base SPLAT exhibits this issue. Really freakin irritating now. Looks like I am going to have to use X3 for any work with my X32 to control the automation weirdness. Is there an issue with Mackie control support with SPLAT? Could that be the reason? Again, everything works fine in X3. This issue is directly related to SPLAT base and beyond...

reported to support - CWBRN-33913

not a single peep from TS about this issue and it is frustrating.

Do you have the DAW remote setting activated on the X32? Try switching that off.

yeah, I wanted to have the X32 control functions within SONAR.

Try running sonar as admin, and try not running it as admin. Make sure windows update is up to date.

Had similar weird happenings to the Track 1, the Master fader and the Main (Left Only) fader recently.
Suddenly dropping to a low level. Refuses to stay back at zero.
Only seem to have noticed this with latest update (H). Though could not be certain.
Tried closing and reloading Sonar. Sometimes solves prob for a while.
Using Mackie Control with Sonar.
Monitoring it before roll-back.

Have you tried unchecking the zero all controllers on stop function in Sonar? Outside chance but worth a try.

Thanks tenfoot for the suggestion.
 
I did try it, and although I cannot say with certainty it was the cause/solution, I have not had a repeat of the problem in the last 24hrs.