Ibanez BTB 675 Preamp issue

Hi Guyz,

I own an Ibanez BTB 675 which is around 1.5 years old. Till day before it was working absolutely fine but yesterday it suddenly stopped sensing any output signal. Like it's completely dead . Changed battery, tried new cable and done all that.
I went to my guitar tech and he said that the preamp is heating up as it is consuming a lot of battery power.
Any possible causes and solution to it?