I measured mine 2 days ago and got 11.5 hours on low gain and no bass boost. @Shane D, all li-ion batteries slowly lose capacity as they age. Look at cell phones - within ~12-24 months the battery capacity is significantly reduced. There’s no way bass boost will cause a reduction from 12 all the way down to a measly 5 hours. It’s clear that your battery has reduced capacity due to age or charge cycles, an internal cell defect, exposure to high heat, or storage for a long period of time in a deeply discharged state such as sitting in inventory for a long time (which causes permanent internal chemical changes to the electrolyte). Was your unit a demo unit, used, open box, or refurbished by any chance? All you’d need to do is install a new battery and it will be good as new.