While developing the HUD-One, I have a little test circuit that I drive - a sort of Nurburgring of RADAR sources. It exposes my RDs to all 3 bands of RADAR and a couple of red light cameras.
Anyway, up until now I've been running my 9500ci with AutoLearn off for reasons discussed elsewhere. Just for snicks I decided to turn it on the other day, and since then I've been getting a lot of falsies automatically stored after only a single pass.
Here's what I believe is happening: the 9500ci increments its internal false alert counters for each location whether AutoLearn is enabled or not; however, if AutoLearn is not enabled, it will not lock those locations out when the count reaches the threshold. If you enable AutoLearn later on, the counters are already above the threshold so the next time you pass that false it gets immediately locked out.
Of course, this doesn't explain the earlier behavior where a source was locked out the very first time I ever passed it, but it might explain the sudden rash of unexpectedly quick lockouts I have witnessed over the past 2 days.