Got a Aiwa NSx-V3000 at a yard sale for a dollar.everything works okay.

Except a song you heard the music okay, but he vocalist you can barely hear.

The sub-woofer was the only thing missing. Could that be the problem??

Or is a setting?? Every component plays okay. The music is great. It's just the voice part it should be louder. The music drowns out the vocal. The two speakers work fine. The sub-woofer was missing
There a jack it the back for one.

Not a snowballs chance in Death Valley.

You paid a $1.00. Did you test the unit before you purchased it?

More than likely the R/W heads are shot. Check with Radio Shack or an Electronics Supply Shop for replacement parts.

Or if the heads are easier to get to, then consider using some denatured alcohol on a Qtip (WITH POWR OFF) and cleaning the heads. Oxide on the heads will do that to a read head.

Let me know how it goes.