Electronic Technician since 1969.
Be sure to use a GROUNDED soldering iron! Otherwise the stray AC leakage might do in the sensitive circuits.
Also because of Europe's phasing out of using any lead in any products[Rohs], the solder is probably tin. Tin solder has a nasty habit of growing whiskers that will short out adjacent pads etc.
We in the USA still can use leaded solder without any legal hassles unless it goes to Europe.
That junk that you saw on the board... sounds as if the flux was not removed entirely.
Be aware that in the winter time in the North the air is extremely dry and static electricity will occur and can damage sensitive electronics either immediately OR[!] later on.
The amount of static that can destroy electronics can be below human perception. So just because one is not going snap crackle pop on carpet does not mean that one is OK.
I should mention... use of lead solder on plumbing is cause for a great sanction from the government.
Last edited by mikeeshaq; 09-27-2010 at 06:24 PM.
Reason: added details