JBL DSC260 led problem

[KevinE]

I'm after help fault-finding on a digital loudspeaker controller, JBL DSC260, which is a modified version of a BSS Minidrive (I think).

 

The input level leds are wildly out of calibration, they don't light up until after the input is raised to digital clip level. The signal present leds work fine. If I raise the input to 3 or 4V the leds do progressively light up but by then the input is well overloaded.

 

The levels in, through and out of the device are correct and the output level meters are all correct.

 

Both L&R are the same.

 

I've downloaded the service manual from JBL but there's no circuit diagrams.

 

Can anyone help or does anyone have the diagrams? It's a BSS OEM product. :)

 

 

 

http://i276.photobucket.com/albums/kk1/kevvywevvywoo/62769f_zpsjpy0e2vk.jpg