403 I/o connections to xlr

Hi @Deadcap, if you need a constant sine, you can use the IDLE button in the Run/Stop group (below the RUN button). When pressed, if you are not making measurements, then a constant sine will be generated at the GEN1 settings (freq and amplitude).

If amplitudes are changing during FFT operations, the FFT result is really hard to interpret. For this reason, there are a few plug-ins and methods that can help. Please see the links below: