My A50s had been on the base station changing for two days when I removed them from the base station as I was working away for 3 days and did won't to leave them on change when I was out the house for a long time . They were switched off on the headset so I would not expect the battery to drain . But when I returned home and came to use the headset the battery was down to one bar . The headset is on the latest FW and was fully charged when I left them . So in 3 days they had lost 3 bars of power . Another day and they may have been totally flat . This should not be happening when the headset is switched off and in such a sort time .