http://www.masterpiece.dk/UploadetFiles/11174/138/Denver_MPG-1013,2013,4013PLL_8-language_QSG_%28ok_19-09-2007_dh%29.pdf
Der står i vejledningen side 2:
CHARGING THE BATTERY
The internal Li-Ion battery can be charged via power adaptor
(option) or by connecting to the PC. The charging
status is shown by the battery symbol in
the top right corner of the display.
Make sure the battery is fu
lly charged before first use.
When charging for the first time the battery should remain
connected to the power supply for 4 hours. In further
charging process, 2 hours will do for charging 80%
for the battery and 4 hours fo
r a full battery charge
Så har du ikke adapteren længere burde du kunne oplade over mini usb stikket tilsluttet din pc.
Så jeg er enig i #1
Men du kan godt risikere den lader langsommere over usb i forhold til med opladeren. Det har jeg oplevet i nogle tilfælde med andre apparater.