Watching a channel on TV (DVB-T) and another on PC (DVB-S) simultaneously

I'm experiencing an issue attempting to watch a channel on TV and another channel on PC (through VLC and Web If).

The problem is that while watching a terrestrial channel(Tuner C : DVB-T) on the TV, if I attempt to watch the stream of another channel(Tuner A : DVB-S) when the stream on VLC start playing I get no signal on the DVB-T tuner ! Why ? 

It shouldn't be a problem watching a channel on a Tuner and another channel on another tuner simultaneously . 

How can I solve the problem ? Is this a configuration issue ? 

Box : Vu+ Duo2 (2 x DVB-S Tuners and 1 x DVB-T/C Tuner)

Image : Latest OpenPLI (with latest updates)

Any help would be appreciated,

Thanks.