JBL Charge 5 battery life

I recently bought the charge 5 speaker for both everyday use and use at tailgates/parties. One of the first times I used it was outdoors at the Rose Bowl and with the speaker playing at anywhere from 80-100% (occasionally less than 50% to play games etc.), it didn't last much more than 3 hours.

I know that playing it at a high volume will decrease battery life, but considering its marketed at 20 hours of battery life I feel like this much of a drop off is weird.

Is this normal or should I look into trading it in for a new one?