Screen Grabbing lags after a couple of minutes

[Schurkee]

I'm using just 40 LEDs for my screen and when testing it works perfectly at the start then starts lagging and slows down after 2 mins it just starts jumping from one color to another after like 5sec in between I tried 115200 baud rate and 500k baud rate same result with 0 difference the only way I found to fix it is to restart prismatik but that makes it useless any help ??

[zomfg]

what framerate? board? and how do you change baudrate?