static

[admkrk]

hey guys,
 just taped my first shows last weekend, and am getting some static(distortion)  from what sounds like the lead mic. i was plugged straight into the sbd. possible problems-
  dirty head/ only seems to come from the lead mic
  too high rec level/ ?
  bad mic cable to sbd/ ?

any suggestions on how i can avoid this in the future?
can i clean this up w/ sound forge?

 thanks.
peace,                                     kirk