Constant voltage of 1,6V at pwm pin 13, 15 and 18

I’m trying to configre a hardware trigger for my Basler cameras.
My cameras need an input of 2.7V to trigger.
I tried to read the voltage that is on the Pins and i get an output of 1.6V,except when i turn off the output and turn it back on it shows 3.3V.
When i tried to connect the cameras I didn’t get a picture until I tried to measure the voltage. Then suddenly it triggered. I can’t explain how this works.

Hi, the voltage level of these pins are 3.3V, if you read 1.6V when device attached, it means the device has a strong strength to pull the voltage low, you need to check the device datasheet for the reason.