skipping problem - Marantz TT-15S1


I just got my new Marantz hooked up. It's sounds amazing, but it skips when it nears the middle of every record. I have tried playing with the counterbalance on the tonearm, but it's had no effect on the problem. Would adjusting the tonearm height help?

Any other suggestions?

Thanks, in advance, for the help.
storguso
Well, i mounted the cartridge before attaching the arm to the table. Do you think this could still be the problem. If so, how would i fix it?

It looks like i am getting shipped a replacement arm and cartridge and i can mix and match and hopefully something will work.
Maybe the bearing is just defective. sounds like you did everything right. just make sure the arm if off the table when you tighten the cart.