KX4Z Turns out it seems to be the PACTOR modem that is bad. Replaced it with one of my backups which N0IA Bud sold me for a SONG just to help me get going --- and it works!!! Two days now and no further "pactor error detected and logged" messages.... So I guess will need some service on the one I had been using..... Bud's legacy lives on!!
KX4Z -- recent onset of problems keeping PACTOR modem connected seemed related to Prolific USB->serial converter, in service for many months. Something changed? Purchased/replaced with FTDI based converter and so far seems to be working better. Just had 45K transferred by user over PACTOR.