Multi Tuner Recording Algorithm?

[preinke]

My current set-up is three Asus P7131 Dual (single DVB-T in each card - I'm not using the Analogue side) cards.

To explain my problem, what I seem to be seeing is:
I have set all recordings to pre-pad 5 minutes and post-pad 15 minutes.
Show 1 is on Channel 1 19:00-19:30 (I'd expect to get 18:55-19:45)
Show 2 is on Channel 2 19:00-19:30 (I'd expect to get 18:55-19:45)
Show 3 is on Channel 3 19:30-20:30 (I'd expect to get 19:25-20:45)
now if I add another show for an existing Channel:
Show 4 is on Channel 2 19:30-20:30
I'd expect Show 2 to be interupted (giving me 18:55-19:30) and then Show 4 would be 19:30 to 20:45.
What seems to happen though is that *both* of the earlier shows are interupted (18:55 to 19:30) and then the next shows are recorded 19:30-20:45.

Is it possible to only interupt (where necessary) the Channel it is already recording (permitting the joining of files later if the break is not at the end/start of the show), or even join the recordings naturally?

Paul

[buckeye]

I am not sure but i remember reading something about the tuner always switches unless you set it not to
i think it a simple matter of switching it off in gbpvr (telling it to use the same tuner )

[preinke]

I've had a look through the config.xml but with little joy (in other words - it doesn't stand out where I should change it).

Any further hints?

[elite]

Code:

<PreferAlternatingCaptureSources>

When set to true will mean two recordings straight after each other on the same channel will use different capture sources if possible, set to false it will use capture sources more economically