ah, sorry - I mixed something. bought a sony bt headset which has an included 550mA USB charger.... my T1 doesn't have one...
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1A won't be a problem as the T1 (as every other lithium battery powered tablet/smartphone/laptop) controls charging current... (without built-in current control, the battery would explode...)
My Sony smartphone will use up to 750mA for charging, if the charger is able to supply it...
So, it seems that with more amps, the T1 manages to charge better...
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compared to factoryreset, battery recalibration can be achieved easier:
https://wiki.mobileread.com/wiki/PRST...roubleshooting