I have finally succeded in a working DVB-T USB stick with pcDuino8 UNO. I have used gstream to stream the channels to local network. But the streaming is unstable. Looking in dmesg i have found out that the obvious problem is the unstable phy (gmac) which quite often resets the ethernet connection. Example from dmesg:
[37693.870127] PHY: gmac0-0:00 - Link is Down
[37694.870115] PHY: gmac0-0:00 - Link is Up - 1000/Full
[38756.890344] PHY: gmac0-0:00 - Link is Up - 100/Full
Internet searching provided me with some issues on similar boards with the RTL8211E chip suggesting some tweaking with tx delay setting ( http://linux-sunxi.org/Ethernet). Yet I did not find a way how apply this tweak - putting it in config file during kernel compilation did not end with any improvement. I am not sure, if this issue is the case, maybe it is originated somewhere else (e.g. power saving options). I tried two ethernet "sources (NETIS router and TP-LINK switch) three different cables, 5 different power supplies, but nothing helped. Is there someone who can suggest what else can be tried to make the ethernet connection more stable?