So, I have this old JBL Flip 2, it didn't turn on, that was an easy fix, however, it stopped producing audio, I hooked up the speakers directly to my headphone jack
JBL Flip 2 Disassembly & Alternative Battery Replacement - YouTube
JBL FLIP II Service Manual — View online or Download repair manual
JBL Flip 2 MicroUSB Port Replacement - iFixit Repair Guide
Amazon.com: Battery Replacement for JBL Flip 2, Flip II Part NO JN151PH13849, PR-652954 : Health & Household