I'm having such problem. Tried different types of SD cards, first one was Trancend 16GB class 10 (high speed). Second one Trancend 8GB class 6 (medium speed). Third one some noname 4GB... So, I've got the same reading problem with all of them; intermittent reading and even card recognizing issue which is rendering SD card reader useless on device. I should highlight the thing that all cards perfectly being read in all other devices when pulled out of Shift and inserted in any of another devices. Tried to do different things, reinstalled drivers few times and so far... Seems this is strange hardware issue (compatibility issue?) arises in windows 7 enviroment. It's so upsetting, I don't want to come back to slugish Vista but I really need SD card reader!
I did not see many posts about it, so is anyone else having similar problem? Can you please share ideas and solutions of the problem if you overcame it.