You might consider filtering out the LAN-to-LAN sites in the inspection rule. If you are using static IP addresses with your ISP you may filter further based on those.
Example - In the keyword section of the inspection rule:
%ASA-3-713119: Group = x.x.x.x, IP = x.x.x.x, PHASE 1 COMPLETED)
It can take some real tweaking to get the desired result. Let me know if you need a more specific example of a rule. Hope this helps.