Control Led-Strip with Arduino and 433mhz modul

I have two Arduinos, one has a transmitter and one has a receiver. First I want to try to control the Arduino with another Arduino, then I will replace the Arduino with a Raspberry pi. And with a local server I can communicate with my phone. But the problem is that i cant control it with another Arduino. It only receives data when the Arduino doesnt do anything else. If I start a effect, it is to slow to receive data