General

Only want certain music on my iPod

Yesterday, I unplugged my CPU tower and took off a panel to vacuum the inside and get rid of all the dust.
When I put it back together, everything was normal (as expected), except for my iTunes settings.
Before, I used autosync to select only the [b]checked[/b] songs in my Library, and it replaced them with random checked songs whenever I decided to sync again.
Now, it still autsyncs anything, and replaces it with anything, even the random stuff I don't have checked.
I can't seem to be able to get it back to the way it was before (autosyncing only checked songs), without making a playlist (which, considering the number of songs I have, would take forever)
Anyone have any ideas?