I am sure there is a simple explanation but I can’t fathom it. I am watching TV via my Hummy and it is recording two programs at the same time. Now I thought it only had two tuners so how is this possible?
As long as the 3 are drawn from only 2 of the multiplexes, this is feasible, just because of the way the channel data is combined in the stream from each multiplex. You'll have to consult a page like this one for details of what's on each multiplex.