Hi Manu,
I tried turning windowed mode on and off with the same result (no change)
I also downloaded the newest version that you released today...unfortunately with the same situation occuring in exactly the same way...
I've been corresponding with S.Williamz and Togtdyalttai about eerily similar situations they were experiencing in the topic "Lag when offline"...
Tog seems to think that it may have something to do with his Google Chrome browser, but it seems indecisive right now...
S.Williamz said that he noticed it when practicing offline in the warmup and we both wonder if it may have something to do with the new match recording/playback section since it seems to have cropped up only after it was added in the last build...

I can live with it by simply exiting back to my desktop after every set/match...like I said, once the point starts the fps rate returns to normal...so it doesn't matter so much when I'm serving...
The lag is most annoying though when I'm receiving serve, as it affects my player's "reflexes" the most then...
