QSC Powerlight 4.0 clipping led on channel

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I have a QSC Powerlight 4.0 on my repair bench with a strange problem. On channel A, when the -10db led lights up the clipping led follows immediately. I have the schematic for this amp. But cant figure out how the indication and clipping led's receive their signal... The amp sounds fine. Only one channel has this indication problem...
 
The first Million Dollar question:
Is the other channel working as expected or does it clip or distort ?
If it plays fine, the problem lies on the Led driving circuit.
I had a similar fault on one "no-named" amplifier but it distorted. I've found an open high wattage resistor open which was feeding the driving stages I suppose because I didn't have the schematics and didn't trace the circuit.
Start by measuring Voltages and check for discoloured hot resistors for a start.
 
Hi MAAC0,

First i thought it was the led driving circuit, i changed out A to B, and B for A. and the problem follows. So the led circuit is doing fine. Meanwhile i found that the low 15 volt rails collapses when output power in a dummy load... The ne5532 power negative rail is going down to 6 volt...
 
On another Behringer thread someone mentions the bootstrap capacitors on those amps go bad. Have You tested the sound output ? Connect a 100 / 10W or more Ohm resistor in series with the speaker or even a tweeter capacitor to reduce power instead of the dummy load. Just touch the terminals a few seconds before the resistor heats up.
 
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