Sounds like you need to be asking DIV for Arty Support (IE SPEND THE POINTS) Ask for some 17cm or above and even if you use them sparingly you should get some Counterbattery Action going. I've found if nothing else this throws the AI's arty off. (Maybe) It's my imagination but it seems to work for me.
Another solution is to ask for more 10.5cm Batteries and lambaste his rear area and or suspected FO/Spotting positions, this has been known to work as well; suppressing the heck out of these guys has the same effect on his artillery.
Bear in mind to afford your Arty Spotter protection as well. Sometimes, it's better to have a safe FO than one who can see everything. This is especially true in Campaigns as your FO gain experience as well; if they are dead or suppressed NOT so much.
Bob out
