audibot

In the last few weeks I have had some issue with my auto transmission. When in D the car shifts fine all the way up to 6 and all the way back down to 3. As I slow down and the transmission shifts from 3rd to 2nd it makes a noticeably hard shift. If I throw the car into S or shift with the paddles it is fine, only happens when in D. It showed up 1 week, than disappeared 6 days laters and returned a week after that. Did some research online and some suggest that the automatic transmission fluid is low. I had a full tranny flush less than 7,500km ago and it has only been in the last 500km that this issue has popped up. Also no check engine lights or any other warning lights on the dash. Any ideas????