Windows 7 won't enter sleep mode - Norton again?

For the last week, my Windows 7 machine won't enter sleep or hibernate mode on it's own after the specified minutes of inactivity. I recall that this same behavior happened after a NS update some time in the last year, and was quickly fixed in a subsequent update. I know there can be many reasons for this behavior, I'm just wondering if anyone else has seen this re-appear since the 22.9 update.