808ROSS,
Thank you for the photos…they are worth at least 1000 words.
From what I can tell from the photos most of the joints seem like they could use some re-flowing. It looks like you might need to turn up the heat on your soldering iron. What kind of solder are you using? Lead/tin solder is the best and easiest to use. Lead-free solder is much more difficult to get to flow correctly and requires much more heat.
If a joint has too much solder on it, then use a solder sucker and remove most of the solder and then re-flow it.
The solder that you should be using has a “rosin core” in it, which is what we call flux. It’s the stuff that allows the solder to flow smoothly and easily. So, when you re-flow the solder joints you aren’t trying to add more solder to the joint as much as you are really just adding more flux to the joint to get it to flow better. You can get containers of just flux; often they come in a pen or marker form so you can “draw” more flux on the joint before you heat it up…but you don’t need that in this case.
I can’t quite see the details of the ISP pins. I can’t see how you might have damaged the PCB there. You can use your continuity tester on your multimeter to check to see if any adjacent pins are connected (they shouldn’t be). Also please check to make sure they aren’t shorted to the ground plane. There is only one ISP pin that should be connected to ground.
When you flashed the software, did the computer say it was able to connect to the microcontroller and was the flash successful?
The fact that you are able to hear something when you short the volume pot pins means the analog section is probably working fine. The problem is probably with the digital circuit.
Keep me posted.
-Brach