i have an HD tuner connected to my mini duo on firewire, and using system_profiler SPFireWireDataType | grep "SAMSUNG ELEC" | wc -l i can determine if it's turned on... however, if it's turned off, there is some period (overnite works, but that's too long;-) during which s.p. apparently caches the device data... is there anyway of flushing that cache?