I have been having random communication problems between my 580ex2 flash and 7d. Essentially the camera was unable to communicate with the flash (if you go flash control->ext flash it says unable to communicate). It happens randomly and after some google search, found and tried the fix below but it only works on one of my 2 flashes. The same 2 flashes worked fine on my old 40d. Is there anything else I can try before sending it to canon?
http://shimworld.wordpress.com …ite-580ex-ii-hotshoe-fix/
