Hi @Pazzo In case the data processing or saving in your loop function takes too much time it could lead to buffer overflow (samples lost/corrupt). You could try opening the device with 2nd configuration to have more device buffer. # 2nd configuration for Analog Disocovery with 16k analog-in buffer #dwf.FDwfDeviceConfigOpen(c_int(-1), c_int(1), byref(hdwf))