I've been noticing this for a couple of weeks I guess, but I had basically ignored it as I thought that maybe I was just doing something wrong. What happens is that when I play matches with the CPU and I am a little in front of the base line on the right side of the court (I play as 1H BH, left-handed), what should be accelerated backhand shots from me are instead average shots that also are just a little short. I am certain now that I have been pushing the correct buttons. I am not out of accelerated shots when this happens. I think that this is a bug in the game. It is frustrating, because the CPU player is very hard for me to beat, and I will have setup perfectly for a hard winner only to have it have be a normal shot. This happens often. I have accelerated backhand shots in many other situations without any issue.