Lights

got a Lezyne Macro Drive front light last week, wondering if anyone else has come across these issues:

• the blinking charge light never turns constant (fully charged) even after more than a few hours. I've just switched it to a USB wall plug thing rather than my computer, in case it's just not getting enough charge.
  
• it makes quite a loud high-pitched hum when it's on. okay so on busy streets it's unlikely to be noticeable, but on quiet roads it might. and in flash mode it's really kinda annoying (eeeee-------eeeeee------eeeeee------eeeeee----- etc)