You could possibly be having a mechanism (tape basket problem) or drum head/motor problem. It is hard to say until it is looked at. A minimum repair could run $230ish. Your camcorder is a 97/98 model.
If you write me at work...I can give you some more info on new camcorders. You can purchase a new digital camcorder starting about $279.00 comperable to yours. It may be in your best interest to invest in a newer updated product than invest in this one that has limited technology.
E-mail me at Ssample@jvc.com and I will get some specifics for you.