[Elecraft] K3 TXF Error

[Allen Bush]

I am just now getting around to trying modes other than cw and data on a recently acquired K3.  I have a 12KHz filter installed in FL1 and the filter utility says it is the only one selected for FM.  However, I am getting the ERR TXF error when I key the mic on FM.  I have no problems on any other modes that I am aware of.  The rig makes called for power and has correct modulation (deviation) on the first mic key on FM but the error keeps the rig from being keyed the second time until I clear the error.    

Any suggestions would be appreciated...   Allen, W0OUU