Interconnect - BER results issues

I’m simulating a simple transceiver (transmitter and receiver) and I want to see the impact of adding km of fiber on the BER. I was expecting that when I add more km of fiber, the BER gets worse but it’s happening the opposite.
Can you please see the attached file and help me with what I’m doing wrong?
PIN_30km.icp (262.5 KB)
Thank you!

Hi @carla.rodrigues,

I think this is due to a known bug that the “fit tolerance” digital filter option soon
t work properly. We are working on to fix this and I will let you know when the bug is fixed. Thank you for bringing this to our attention.