The first time you configure the ExpertSDR all the configuration options can be overwhelming. To get you started fast, here is an explanation of the audio tabs and their settings for a SunSDR2 transceiver.
The settings are similar for the ColibriDDC, but without the transmit settings.
Microphone input routing audio through AGC, TX Equalizer, compressor etc. Working in the same way as the real inputs on front panel.
This output is the same as the headphones output on front panel. Audio from this output has gone through RX Equalizer, Volume control, Balance etc.
The same as Souncard, but Volume control is not active (fixed level of all signals), TX monitoring is always ON.
Only for digi modes. Provides the ability to adjust RX and TX audio levels, but not using RX EQ, TX EQ, TX AGC, Compressor etc. Linear transmit and receive of all signals.
Smart PTT control
If VAC is ON, PTT signal from PTT footswitch or PTT COM port (Footswitch), or PTT from E-Coder, signal will passed to transmitter from MIC inputs (MIC1, MIC2 Mic PC) — NOT from VAC. If PTT signal came from CAT-system, or CJV port PTT (not Footswitch COM-port), CAT system signal will be passed to transmitter.