Like Ken said, you need to go into a terminal program and change the Audio Gain setting. This is covered in the QDX operation manual, if I recall correctly. I have had to increase mine on higher bands, especially.?
WJST-X calls for the user to "?set the background noise level (scale at lower left of main window) to around 30 dB when no signals are present."
?
-Nate
N8BTR