I looked closer on the messages but it seems that the specific bit errors are always "0" that are changed into "1" in Labview. I can find no discernible pattern between the position of the errors as they seem random.
I also tried two other terminal softwares (Realterm and Moxa's own PComm), which both gives the same kind of errors for the same settings as I successfully can use in Termite. Perhaps Termite makes some sort of message correcting that is not performed by the other programs.
For now I can make due with Termite, forward the signal to a virtual port and use that virtual port as the input COM-port in Labview to get the correct formatting in Labview. Not a real solution, but serves for now.
