Please let me know if you connect okay when dialing the 1543 line direct. I flashed its rom but since it is a 4b rom it will only do 28.8. The update however is supposed to improve connectibility with other modem types. I left the settings default.
I have been disabling MNP5 on the 1543 modems so you Robotics guys can log on and get reasonable transfers. If the trouble has gone away I would like to leave all of the modem features on.