If done in a dark room, you can see the flash from under the PCB, then desolder the affected cap, shake it out of the board, and install a new one on the reverse side. The increased voltage and current delivery snaps the shorted cap right open. We modded our test PSU with switches for each bipolar rail to supply the unregulated +/- 24V or so BEFORE the regulator, to drive the board. I learned this technique right from Behringer's lead tech when I was in Germany for training in 2001. If you have a shorted cap in the board, the easiest way to find it is to 'smoke it out'. What killed most of these IC's was poor thermal transfer due to improper factory assembly. If you replace them, make sure you use heat sink grease and torque them down snuggly. If the IC is bad, it will usually be bad unloaded as well. However, as Doug pointed out, you could very well have a shorted bypass cap on one of the mixer PC boards.

Usually, it's one or both of the LM350T's. Not all manufacturers distribute schematics to the public, but some of us stand there and curse the darkness, while others light a candle. Google for the schematic, and as always, try Elektrotanya. Look at them closely, any have black marks on them? Power and Sound The Behringer MX8000 is powered by a 400 watt external 19-inch power supply that is connected to the back of the console. Once that far, a schematic won t help anyway, each IC has a small bypass cap by it, one of those shorts and you have to track it down, the schematic won t tell you which one of hundreds is the short.

If the desk is indeed loading the supply, inside ther are large boards making up the whole deal, each can be disconnected from the system to try to isolate which board has the problem. But it must be checked under load, you can t just plug in the power supply alone and measure its output. On any large mixer, when all the peak lights come on and stay, and sometimes the VU meters max themselves evem, it almost always means one of the power rails to the op amps has failed.

Behringer mx8000 manual