I noticed the sampling rate for some of the models is half when both channels in used as compared to when only one channel in used. For example the 5000 series, it is 1GSa/s when one channel in used, and it is only 500MSa/s when 2 channels in used. Is this related to the number of data acquisition units used inside the unit? I was guessing 5000 series have only one data acquisition unit and it is shared between both channels; while models like 3000 series, they have 2 data acquisition units inside. Is my assumption correct?