Corrupted TX bitstream when FX.25 enabled

[dvanderlocht]

I have observed that a TX bitstream gets corrupted at random places with FX.25 enabled.

Initially I thought there were problems with the receiving side (AX.25) but analyzing the HDLC bitstream showed me the bitstream is getting corrupted at the TX-ing side (Direwolf with FX.25 enabled). The issue isn't there when FX.25 is disabled / plain AX.25 is used.

Receiving stations with FX.25 support mostly can correct the wrong bits and don't seem to suffer.