Emg problems luke bfr koa

[blackmorse159]

Hi, i have a mm luke bfr koa with emg pickups but recently something happened about the sound...when i conect the guitar to Amp its sound with less volumen..but when i disconect and conect the batery it sound more powerfull ...its a new battery... why happened that?? Some ideas?

 

[blackmorse159]

I have to say it sound powerfull but just for a minute... i change the batery but still the problem