Just a quick question

[dyzombie]

So I built a big muff, from all the GGG specs and I even ordered their PCB board because this was my first build.  When I finished it, I plugged it in and it worked perfectly.  But then a few days later, it just stopped working.  The sound still goes through it just fine when its off, and when I turn it on, my LED lights up, and I get some feedback, but no actual sound from the guitar.  Does anyone know what could be causing this? I really need this fixed by tommorow, so thanks for any help I can get. 

[Hides-His-Eyes]

It's the broadest question in history...

Have you:

Inspected for damage

if nothing's visible:

Build an Audio Probe (google it) and find out where the signal is lost

common causes might be:

plugs in backwards
bad power
component fallen out of socket (resocket all your components that aren't soldered)
Board grounding out against the enclosure