No longer sleeping

Well...
Out of the blue my HTPC will no longer sleep.
Has been doing so previous to this.
Hope someone with knowledge will have a look-see at the logs and give me some direction to solve this issue.
Cheers
Ventry

Sorry but, that one I manually put it to sleep and woke it up with my Hauppauge USB remote.
The problem was before that.
I had been trying to find the problem.
It has been set for sleep after 5 mins of inactivity on the Home screen only.
I had it on said Home screen and watched it for about 30 mins without any activity and no sleep.
I did a full reboot and watched it for another 15 Mins on Home screen no sleep.
It used to work fine. I changed nothing.

P.s
Computer set to NOT wake by mouse or keyboard.

Ok here are tonight's logs.
I finished watching TV and went back to the home screen.
It should go to sleep after 5 MINS.
It has been over 45 MINS and no sleep.
Interesting is that when I exited MP to collect logs it went to sleep half-way through that process. (about 1 Min after MP exit)
This would indicate that it's MP itself and not the TV-Server right?

Update:
After some playing around it seems that the "Network Activity Monitor" is the problem.
It was (and has been) on.
Now if I turn it off sleep occurs normally.
If it is on despite NO network activity (I watched my router) then sleep doesn't happen.
This is INFURIATING!!! It used to work!!!
I never touched it and it stops working ALL BY ITSELF??????

Thank for the help.
I will have a look at the things you suggest.
However I will point out that the section of the logs you have posted has the time stamp "18:41:33" which is 6:41 PM.
The HTPC was in use at that time watching TV and I believe that TV Series was updating the database at that time also so, the HTPC would not have slept anyway.
My biggest problem is when finished watching for the night, go to bed, get up next morning and the HTPC is still running. The only reason my HTPC should wake is for recording.
Cheers
Ventry