Especially most of Czech DVB-T2 multiplex 13 channels are absolutely silent. I tried switch audio track (some of such channels have only one), audio language setting, different HDMI cable, plug different TV, tried multiple images (VTI, BH, OpenATV), but no success 
I've already noticed same issue from another people (no piece bug).
It's maybe some "multiplex specific" issue on broadcast side, but other receivers, including E2 (Octagon SF4008, Dream DM900 ...), work well (no such issue). I guess it's a software bug and it must be solved (it's totally useless). Could any of developers test DUO 4K on Czech DVB-T2 13 mux (at K24 in Prague)?
I've already noticed same issue from another people (no piece bug).It's maybe some "multiplex specific" issue on broadcast side, but other receivers, including E2 (Octagon SF4008, Dream DM900 ...), work well (no such issue). I guess it's a software bug and it must be solved (it's totally useless). Could any of developers test DUO 4K on Czech DVB-T2 13 mux (at K24 in Prague)?