I have a HCH, '05, I've been using the carpool lane on the Bay Bridge since late last August, when I got my stickers. I drive into San Francisco 4-5/x weekly.
I've called FasTrak a couple of times on this, they tell me the charges sometimes show up late (and, sometimes, they do) but figuring it out, over the past 9 months, there's alot of my trips in that are never charged for (last week, as example- 5 trips in, charged for 3). I got my bill last week from late Feb to late May and the months of March and April were way undercharged.
Is anyone else seeing this?