Alright, I've got a 430EX II Flash, and I've had it for 3-4 years and I normally just regular AA batteries like the Energizer brand.
Everything works for the first 5-10 shots, the flash goes off as quickly as I press the shutter... then after 5-10 shots the delays begin and sometimes it can take up to 45 seconds for the flash to power back up and flash again. I'll put in new fresh batteries and the flash is great for another 5-10 shots, then right back where I started.
Is it the batteries? And if so, what batteries do you guys prefer for your flashes?