If the drivers for your soundcard aren't much good then you will get some latency (lag) on the signal as it is processed. Adjust buffer settings and latency slider until you can play with low latency. About 20ms is about the max you can get away with.
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Ansy helped me out with getting my guitar to come through my computer, but now I do have some lag... How do I adjust buffer settings and latency slider - I dont even know what these mean... thanks