sometimes i can leave the same battery in the phone and charge it every night. then all sudden it starts acting up, lagging, changing dates, freezing up alot. when i restart it it always wants to know if i should send message to htc. saying the phone was improperly shut down, i shut it down the correct way. when i change batteries, the phone lags, freezes up alot. its getting really bad where i can't even rely on the phone anyone else have this problem???? when should the batteries be replaced?