I've just noticed a behavioural difference between "DVB/driver" and
"dvb-kernel"
(I have temporarily removed my grundig mods in case it was that)
If I do "dvbtune -f .....", and then "dvbtune -m", in DVB/driver,
this works fine,
but in dvb-kernel, it "loses" the the tuning after about 4 seconds.
Similarily, dvbscan (from dvbsak) has problems with dvb-kernel.
Could this be something to do with not keeping the frontend device open?
Spotted the problem. in "DVB/linux", if "fe->dvbdev->users" is non-zero,