On the subject of tuners I got a GigaBlue DVB-C/ T2 (H.265) twin tuner module for UHD Quad 4k, UHD UE 4K & X2 installed when I bought my gigablue is there any advandage if I am only using one terrestrial feed and does it have passthrough i,e, take output from second connector to aerial port on TV. or is second connection for cable only.You can combine two aerials down one wire using a diplexer, you don't need two tuners. Also, Enigma2 treats all DVB-T tuners as the same, you cannot tell it to use Tuner A for Mast A and Tuner B for Mast B.
With regards to the clash issue mentioned on the website that Urie pointed to, You can set Ignore dvb namespace subnet to "No". The clash should be avoided.