Hello AS.
I have had the A318/A319 and A320/A321 since the release. But just suddenly couple days ago I started to have this extremely annoying problem. At the final approach phase, when the SPEED mode is active the thrust swings up and down. This causes the failure of the FMGS to maintain the VAPP and it goes too low. Taking the thrust to manual control it still looks very wrong and weird.
So to demonstrate, I did a quick video for you. Here is the link: http://youtu.be/ktduzyst3EU