Clean your jacks and plugs on all your cables. Oil can accumulate and lead to static when the connection is turned in the jack. Easily repeatable at home... Plug in, power up, set record, monitor w/ phones, and twist cables....
If this is your prob, get some 92% alcohol at the drug store and a dental/gum brush (oralB with a cap), clean both jacks and plugs. Do not get extra alcohol in the player, gravity should be your friend not your enemy (brush up in the air, deck upside down).
Hopefully, it will be this easy and cheap fix. Oh yeah, QUIT touching the bare metal of all your plugs......
Good luck,
Joe