The crack was my first real project, and I got through it with no real problems. All the voltages and resistances check out. But now that I'm using it, every so often its like the sound disappears into the back ground. Its hard to explain, but the low and mid frequencies are distorted and far in the background while I can still hear the highs are still quite audible but kind of distorted. I have no idea whats going on, any help would be appreciated!