I was troubleshooting a circuit today and tracked it down to excessive reverse leakage current (1n4005 diode). Checked fine with diode function on DMM, however I suspected it was flaky and found reverse leakage to be about 10uA @ 10V and 30uA@100V at room temperature.
These are probably about 30+ years old. However the device looks like new inside, must have been kept in a clean lab.
Does anyone know the contributing factors that cause this? Age, transients, humidity?