I personally use a freeware product called
Alternative Flash Player Auto Updater to update Adobe Flash.
Now I do not like that it runs in the background all the time so I do disable that part. I personally do not have it in start-up, when I choose I start the application, run it to update flash, and then I tell it to close.
But I like that it checks the current version and shows me that and the newer version and updates all my browsers. To me it seems to avoid some of the update issues and from what you have said it might be worth a try on your machine.
If you are going to use this product then when Adobe installs it is a good idea to choose Adobe's last option to "Never check for updates", instead this program will do the checks.