Solid state amp goes "pop" then no sound, but works again after power cycle.

[reefus01]

Hi Y'all

So I have Behringer GMX210 solid state amp that will operate fine for anywhere from 2-10 min and then it will suddenly make a sharp "pop" sound and I lose all audio. The amp still has power and all the LEDs and indicators still light up like normal, just no sound. If I turn it off and wait a little bit to turn it back on I get sound, until it pops and goes out again a few minutes later. Any ideas what is causing this and how to repair it? Any help is appreciated! Thanks!

- Keith
Portland, OR

[Enzo]

When it does this, poke a plug in and out of the FX return jack a couple times. Did that wake it up?