Avoiding the tuner on a broken FF card

[gdh at acentral.co.uk (Gavin Hamill)]

Hi :) 

I have a FF DVB-C and a budget DVB-C, (they're both ves1820 devices) and the 
tuner on the FF card is v unreliable - I would like to avoid using it 
entirely.

Is there a magic one-line hack for VDR to bypass the device-selection logic 
and always use a specific device, and hence always force transfer mode from 
the budget card to the MPEG decoder on the FF card?

Cheers,
Gavin.