ZIP Drives and Vista

I recently installed a new ZIP 750 ATAPi Drive on the vacant IDE controller
of my PC. It seemed to be working ok but sometimes after the drive spins
down Windows can't access the files reporting no disc in drive, with the
drive activity light flashing 1 per second, attempting to access the disc
causes the light to flash at twice that rate. This seems to be an
intermittant problem, if you have experienced this I would like to know if
you found a solution and what it was. Thanks...