[cybmole]

what he's describing seems to be a T1 sleep bug - may be answered already somewhere on Sony forum, but as the forum stupidly will not accept "T1" as a search term" it won't be that easy to find.

I have read stuff about battery drain during sleep when researching battery life for the older Sony readers.

as I recall there are some hard to explain issues but which only affect a small proportion of users.

I doubt is has any connection with calibre but my proposed 2 tests would prove or disprove that.

when I have experienced unexpected battery drain is was due to me leaving the reader to put itself into auto-sleep but then some bit of fluff or feather on the screen preventing that happening, so that it was drained next morning. There was an argument going around on Sony forum that excessive use of the power slider on older models would cause that to fail so it was better to rely on auto-sleep - but not when you have active budgies!