Block HTML output cache needs refresh from time to time

[ADDISON]

I am the only administrator of the store. I am doing before night a "Flush Cache Storage" in order to get the following issue. In the morning I visit again the backend and there is a warning message "One or more of the Cache Types are invalidated: Blocks HTML output. Click here to go to Cache Management and refresh cache types."

Blocks HTML output warning reacts once you make changes in backend. Is anyone knowing why "Blocks HTML output" cache needs a refresh after a few hours without touching the backend?

[nohart]

I get this every day when I wake up and sign in on Magento v1.9.2.2 - One or more of the Cache Types are invalidated: Blocks HTML output. Click here to go to Cache Management and refresh cache types.

I never used to get this on earlier versions unless I was actually doing something. Is this some kind of bug? It didn't used to do this with Magento v1.7.02 and we dont have any additional cron jobs running that I am aware of.

[Travis_Mc]

I have this error message every morning too.  I know it's a nightly cron job that causes it, but It breaks my SSL for my facebook like box.   I'd like to figure out a solution to this.