For typical studio work, I shoot with a 40D connected to one of my AlienBee strobes via the PC/sync port. This worked just fine, until recently. Now, the strobe will randomly not fire, and it's definitely the 40D. My old 20D body works fine, and I've tried different cables and strobes - it's definitely isolated to the 40D body. The most maddening thing is it's completely inconsistent. Sometimes it will fire only in vertical grip-up orientation, or if I'm holding down on the plug a certain way (which is rather annoying anyway), but only for a little while, and then it will stop or start working even if nothing has changed. I've tried screw-in cables - doesn't help. I've cleaned the contacts, tried just about everything. Anyone else have this issue? I hate to have to send it to Canon for something like this, but I'm starting to get the feeling I'll have to.


BTW, is it me, or is the PC/sync port just an engineering failure? It doesn't seem to be particularly optimal to me, compared to most other connector types I've used for various applications.