I replied privately before I realized hans-peter posted here as well.? It echos what Willie said.? As follows:?
Hans-Peter, if you take a look at the operation manual on page 17, section 4.4, you will see that there is an "audio gain" number.? I have mine turned up to maximum.? Give that a try.? Default is 5000, mine is set at 99999.? That should give you stronger signals for FLDIGI.? At that setting, JS8CALL still works fine for me as well.
Joshua
Joshua KJ7LVZ