If you have tried it on 2 different pcs using the same operating platform and it does the same on both, it has to be a driver issue or an operating issue with the particular easycap you have purchased.
Why would it do it in XP and not Vista? You would think it would be the other way round.
Try downloading drivers and reinstall from the downloaded ones.
DC60 drivers:
http://www.ezcap.tv/DC60driver.rarHeat from the device.
They are normally warm, not hot. If it is getting hot it is a sign of a very cheap circuit board.
That's the problem with fakes, they are all different. You do not know what you are getting.