Latency is not an issue of the particular software, but of the sound card drivers. An ASIO driver means the audio goes straight to the sound card instead of going through the operating system. In windows, for example, I've managed to reduce my latency from 44ms using the normal driver, to something like 5ms. The downside is, the operating system can't do a mix of each application's sounds, so when I have some program that uses ASIO, all other sounds are muted. Also, in my case, when an ASIO application starts, it "asks the operating system for permission", so if there's something else making sounds it will refuse to work (typically I have to close Windows Media Player in order to run Propellerhead's Reason. If I don't, then Reason can either choose the normal 44ms latency driver or nothing at all). ASIO4ALL, like another user suggested, is a really good choice as it seems to support many cards. Note that installing an ASIO driver for your card will not uninstall other drivers, so you can still use the OS' regular way of doing things (which is what allows WMP and say Chrome to output sound at the same time).