The part you need is: SA-HM14PA0300-B
That'll get you the small PCB with the charging jack (new part).
Costs ~ $9 + shipping
Call JBL Tech Support @: (800) 336-4525 (also on JBL support website - link below)
Last I checked they still had a couple in stock.
Note: You'll need to de-solder/re-solder the wires back to the replacement part, so find help if you don't have soldering experience.
[https://www.jbl.com/support-product.html|https://www.jbl.com/support-product.html]
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