AC0KC, a good pal of mine, just built a "son of the softrock" SDR, and it didn't work very well. Quite deaf on RX.

Took him a few days to find a solder problem on an op amp. It looked good and tested fine with the ohm meter.
But with current running thru it, the voltage was off on the op amp. Total PITA. Whew.

I don't have much time to fix stuff, and when I do, it's for the brokedown palace, or computer stuff. ;)