if you have a 6.5f to 3.5m adapter, try plugging the guitar straight into the mic in of your sound card. You may have to turn on the mic boost thing in windows volume control. to get enough signal. If there is no noise then the guitar and lead are fine, the problem lies in the mixer/leads side of things. If the noise is still there the guitar lead could be damaged, or perhaps the pickup itself is damaged, at which point, id take it to a shop and get it looked at. Really small fiddly things arent my forte, if i cant fix it with a 3/8 ring spanner its too precise for me
