Alien Bees Slave Issues: Any Ideas

I am posting this query for a co-worker who just purchased 2- Alien Bee's to photograph art work. He has a hot shoe sync connector on his camera with a sync cord connected to one of the Alien Bee's and it fires when he triggers the shutter, however the second Alien Bee does not fire as it should as a slave. He said both units do fire independently when connected to the camera via sync cord, but neither one fires as a slave. I asked if he has a plug plugged into the "slave" unit which would disable the slave function and he said no. I also asked him to trigger the flash at the back of the second unit, which he did and when fired directly, the slave unit does flash. He called Paul Buff and explained the issue to them and they said unless the slave unit sees the flash it won't trigger which is correct of course But why would this be an issue when both units are in the same light colored room, only a few feet apart. They suggested he either get a hot shoe sync connector for his camera with 2-sync connections or get Paul Buffs wireless Cyber sync transmitters and receivers. I am baffled as while I have not used Alien Bee's I have used not only many different studio flash units, but years ago I had Paul Buff White Lighting units and never have I had the slave units not fire. Any ideas, appreciated?

I don't know about the Alien Bees, but the Einstein's require the optical slave to be enabled in the options menus. I would think the standard Bee would have something similar.

Unless there is a plug in the sync port the bees fire as slaves by default. I would suggest firing them at each other so there is no issue with line of sight.

gonzogolf wrote in post #17265384
Unless there is a plug in the sync port the bees fire as slaves by default. I would suggest firing them at each other so there is no issue with line of sight.

Yes my initial thoughts and he told me there was no plug in the sync port and I asked him to fire at the back of the other, which he did and both fired as slaves.