Sandisk Sansa e260 Every time I connect to either my computer or ac charging line, I can't get out of the charging mode. Has worked fine for months, but now can't use it. If I just disconnect it, I can't turn it back on. It play my music as long as it's connected, but can't turn it on without either ac power or computer. BATTERY ISN'T DEAD, unless it had a very quick failure.