can't switch to ati capture driver as primary tv capture source in mmc 8.7

Hi,
the only thing i want to do is to watch tv with the mmc!!
following problem:
in tv configutation i select "ati WDM Rage Theater Video" as primary
capture source - (which is installed and shown there correctly) but
when i want to watch TV with mmc via composite-input i get only a blue
window - when i go back to the configuration menu again - the primary
source always stays at hauppauge capture driver. (i have also
installed a Hauppauge WinTV pci card)
OK - the apparent thing to do is to uninstall the hauppauge card and
all drivers and software - which i did - but then mmc does not start
at all and i get this "TV Player Failed to Initialize the Video"
message!
So it seems i need the hauppauge card to get mmc started but with the
hauppauge card i can't use ati as primary capture source!
schizophrenic isn't it!
So how can i make mmc to use only ati WDM Drivers as primary source?
i want to uninstall the hauppauge card completely and only use the ati
card - but untill now i need it for watching TV.
With other capture applications (e.g.virtualdub) i can use the ati wdm
capture drivers with no problems. i did all the installation stuff
according to the infos.
so untill now the only way to avoid the problem is: to use WinTV as TV
viewer and virtualdub with ati capture drivers to capture video - but
then in always have to change the composite input cable - from the
hauppauge card to the ati card.
please help
manfred