If you are referring to the tick box in Settings->Community, then that setting is sticky here. I unticked it and it has stayed that way since shortly after I installed 2014.9.0.2008, despite many reboots.

If your setting isn’t sticky and keeps changing, then my question is how did you do your last program update. If you updated from version 8 to version 9 (2014) either via the program itself, or by manually updating over the top of the previous version, then I would suggest you consider downloading a new copy of the current version, then uninstalling Avast in safe mode using Avastclear.exe, rebooting, then doing a new install.