Simionic G1000 com frequencies

At EGPB the tower freq is 118.255. Whenever I try to set this freq via the Simionic G1000 app it automatically changes to 118.250 less than a second later. Channel spacing is set to 8.33Khz on the app as well as on the G1000 in MSFS2020. This problem does not occur when not connected to FS2020 so my guess is that there is a problem with the Simionic G1000 bridge or FS2020. Does anyone has the same problem? Please help. Thanks