#1
Didn't think this belonged in the GG&A but tell me if it does.

Quick question about my set of headphones, over ear variety. The right cup stopped producing sound a while ago, and I've taken it apart this evening to have a look and noticed that the solder connections between the wires and the back of the driver have gone dull which means there's no current coming through.
Is there a way of narrowing down where the problem might be? It's definitely the headphones that are the problem, and I've tried moving the wire where it joins the jack and there's not even a crackle to suggest a loose joint in there.
#4
Continuity test on your multimeter to see if there's connection through the solder joint.

Don't let your boat be empty, don't be a sunken dream
Don't let the boat regret thee, for what you could have seen

#5
Also just noticed on the off chance that one of the insulating rings around the jack pin has got a small chunk missing from it (only about 1mm or so) would that likely be the problem?
#6
If it's shorting between the conducting parts of the plug? Again a continuity test between the two points will tell you.

Don't let your boat be empty, don't be a sunken dream
Don't let the boat regret thee, for what you could have seen