I need some advice. I can't seem to get my FD so that it doesn't drop my chain on to the BB shell.

A year ago I switched from a standard to a MegaEXo 50/34 compact the FD is a 6500 double. I remounted the FD and shortened the chain. It seemed to work OK for a while but I keep getting chain drop about once per ride a few percent of the downshifts. I've tried adjusting the limits and even with the L screw set so tight I have chain rub on the lowest gear it still happened. I also took off the FD cleaned and lubed all the pivot points and remounted it as low as possible without hitting the chainring. It still does it.

Any tips? Could it be the Housing is worn? Should I try raising it or rotating it to a different angle?