baechlju:
I am making a lighting for my room with a 5 meter, 300 LED's strip.Maybe it's because i bought a 3€ arduino and a even cheaper bluetooth module.
It probably isn't. It might have something to do with power handling, and throwing money at Arduino or Bluetooth is not likely to fix it. It might be better spent on the wiring, about which you say nothing. Please post the code in the proper manner, using </> tags.