DG4000 Calibration Restoration:
Re. Sniffing the Rigol's internal I2C bus, Reply #1771
I now believe that the Restoration of the DG4000 calibration should be done for AC, LFLAT, and HFLAT to correct some other potential glitches. Nothing is being changed, or has to be connected to the DG4000, so the process goes fast. Just bring up and save all the default values for each step, starting with 1, or 1-1 (A/R).
You can also do this for 'Inner Imped' and 'Offset', although I haven't seen a case or benefit for it yet.
I just wouldn't do this for Freq Accuracy, or Counter, unless you see a need for it, and then you should complete this cal. process as prompted.
The calibration restoration is effective for both channels, so it isn't necessary to repeat each cal. routine for the other channel.