Monthly Schedule Running Daily

I'm new to this forum and have looked around to see if anyone else is having this problem, but haven't found anything. Hopefully this isn't a repeat of a previous question, but if so, my apologies.

 

I'm running Symantec Antivirus 10.2 on a MacBook Pro running Leopard 10.5.7. Recently, I created a task in the Scheduler to update everything once a month (I don't know why I didn't have it before, I could have sworn I did). But I've found that LiveUpdate seems to be making contact every single day -- I can observe the network activity with Little Snitch. I used the command "symsched -l" from the Terminal and the schedule entry is there properly, i.e. listed as "Monthly." I'm not quite sure what is going on, but it seems as though only if I delete the scheduled task (and it's the only task in the Scheduler) does LiveUpdate stop trying to phone home every day. Is there some easy fix for this, like deleting a prefs file that might be corrupted, or something to similar effect? Any and all help is greatly appreciated.