Quoted from netman63129:
I ended up swapping out the stock 3/16" post rubbers for 3/8", which is more the standard size I see on most machines anyway. This seems to help with some of the cheap drains. As other have mentioned, increasing the playfield pitch would also help but I think that mine is high enough already
I found out today that putting a 3/8" rubber on the right post at inlane/outlane location, causes the ball the get stuck in the outlane. It's fine on the left side though.