Receiving Different IR Codes From Same Remote/Button

I had the same issues.
I could "fix" it by changing the voltage to 3.3 V and decreasing the distance for the cheap remote.
Other remotes (e. g. Onkyo Receiver) work just fine with 3.3 V but not always with 5. The LED on the Arduino board blinks regularly, instead of the irregular blinking while using the cheap remote.