Behringer Europower PMX2000 clipping

[auditoriumb]

I assume the PMX2000 has automatic circuit protection that cuts out the amp if you push it too much. Mine started clipping out a few shows ago and got progressively worse. Now it will cut out at very low levels. If I plug directly in to the power amp input from another mixer it is fine but if I run through the mixer/preamp, it cuts out frequently. Any idea what the problem is and how to fix it?

[Enzo]

My first thought is a collapsing 15v power rail. or a failing op amp.

The only place needing protection from clipping is your speakers. The power amp will have overcurrent protection and a crowbar across the output for DC. But the power amp works. SO the mixer would be the problem if powr supply is OK. if all input channels are affected, then I l;ook in the master section