"Customer is not happy with the bass quality." verbatim reason recorded when I returned JBL Tune 115TWS. Bass is non-existent. Maximum bass adjustment on music app equaliser and these still sounded unbelievably tinny. Literally 5 minutes to try and know they were no good, back in the box and returned. I used the credit and spent a bit more to purchase Sony WF-XB700 instead and the Sony sound fantastic (bass on equaliser slightly up for \m/ music).