PedalShield Uno Troubleshooting

Hi,

I'm fairly new to this so bear with me. So, I made a pedalshield uno and I tested out to see if the signal is passing through it or not, and it does. So, I know the problem isn't connected to the electrical components. The problem is, all I get is clean input, and the effects that I uploaded onto the arduino won't trigger. Would anyone know the reason why? The output is clean and no drop in volume or anything occurs. I'm guessing it's a problem with the connectors, but I could be wrong.

Edit: Not sure if this would be useful information or not. But, whenever I'd have the pcb connected to the arduino uno, the serial port would become unrecognizable to my computer. However, with the pcb off, it becomes recognizable again.

Edit 2: Actually, I think I'm not getting any sound at all. It's just white noise. Just realized that when my pedalshield is off I'm getting sound. Talk about embarrassing, lol. But yeah, so I guess it's a problem with the pcb. I guess I fried some of the connections or soldered something wrong. Here are pictures.

Edit3: Tried the sine wave code and it generated sound and worked perfectly, so i'm guessing there's an error with the code im running?

Edit4: I was testing my circuit more, and whenever I run a computer generated wave I get the desired output with no problem. However, whenever the effect is dealing with guitar input I get nothing. So, there's a problem with my circuit, somehow the analog signal from my guitar isn't getting through.

Edit5: I desoldered the op amp because it looked like the soldering might've caused a short circuit. But no output still if I plug my guitar in .

Edit6: I desoldered a few more bad connections and sorted them out. Works now!

PS: All those edits make me look crazy, lol.