newbie to vinyl needs help

after alot of reading i finally took the plunge and picked up a vintage technics sl-bd22 turtable on the CHEAP..as in$35.... First thing i notice is WOW i like the sound...BUT.... There is a very noticeable and nasty distortion in certain upper freq. Mostly i hear it in voices "s" and "f" sounds and some cymbals. I have replaced the stylis with no improvement...I would replace the entire cartrige(audio tech.) however ive been told that they either work or they dont so replacing it wouldnt help. Im not sure if I just have a junk table or if the problem lies elsewhere....ANY advice is apreciated!

My equiptment...

Magnepan 1.7
Onkyo pr-sc 886 pre/pro (has phono imput)
Anthem mca5

Thanks in advance,
Randy