problem with "show unread posts since last visit"?

[meester fox]

I woke up this morning to look at my site, and I clicked that link on my site, and it returned no new posts.  fine. so i went to the index and to the board where i wanted to post... and it turns out there were 4 or 5 new posts that i had not seen last time i was there.

this isn't the first time. I've been suspecting something wrong in this area for a while. Something (with my 1.0.1 at least) is wrong.  Any idea's on a fix for this, or, anything?

note that, i hadn't visited the site for a few hours.  a new post icon was displayed next to the board, so that worked.  And later today, I checked again, and someone made another reply. THIS time, it showed up as unread replies.  I'm puzzled, really. could it be something with a few users and their settings?  Why doesn't it do it all the time, only a few?

[[Unknown]]

Have you tried looking at "all unread topics"?

-[Unknown]

[meester fox]

Yes, that works. it shows me all the topics I haven't read.

Is the "show unread topics since last visit" not that reliable, or something? or... what? I just don't get why it works SOMETIMES.

[Jerry]

do you use SSI in your pages? when I used to use SSI in my pages it would also make my unread replies since last visit not work correctly. I just figured SMF was counting as visiting the page with SSI as a visit to the forum also...

[[Unknown]]

It starts the visit when you visit an SSI.php enabled page, yes.  And, if your sessions are not set up properly (e.g. there's a space before the include to SSI.php or ANYTHING) then that can count as a visit too.

-[Unknown]

[meester fox]

Ok, that makes sense.

But, would this be the explanation?  If I don't visit my site for 8 hours or so, and then visit it, is having SSI on the front page of the site, causing "show unread posts since last visit" to not work?

and yes. i am using SSI on the front page of the site. 

So in either scenario (SSI causing it or not) what steps can I take to stop this problem from happening?