2 different pro mini's producing different results

Using Arduino Microcontrollers
1

I have an Arduino sketch for a transponder that's sending a PWM signal to a transistor driving a Ir led.

I have 2 different pro mini's 328p and a pro micro's that all produce different output levels. 1 pro mini works flawlessly, the others Only once and a while. Any suggestions?

2

Where are the links to the Pro Minis?

What sketch?

Same wiring, what schematic?
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