No, after I cycled both the flash and camera on and off it would work fine for at least five more shots. I haven't tried it with AAs though. I've only run it with AAs and the TR-Pak IIa NiCd battery. Is the 4000 compatable with external power? The only permanent damage my EOS 5 ever sustained was a command dial failure - still haven't fixed it [img]/ubbthreads/images/graemlins/tongue.gif[/img] It's odd how it works flawlessly with a newer Elan 7e but locks up with an older EOS body. I wonder if Sunpak could offer any information regarding that? Haven't had one hiccup shooting them off-camera in manual mode with Pocket Wizards. My Sigma flash doesn't function with them [img]/ubbthreads/images/graemlins/frown.gif[/img]
-Richie
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