Canon Battery Pack CP-E4 and Micro Sync glitch?

I have 2 external speedlites, Canon 550 and 580 II that I sometimes use for shooting birds, along with a Canon ringlite macro flash. I trigger with a MicroSync transmitter and 3 receivers. Two receivers are older original ones and one is the newer "II" model. When I hook the battery pack to either the 550 or 580 (doesn't work with the ringlite) and use either of the older receivers, all is normal. But when I attach the newer receiver, the flash starts firing randomly, all on its own. (Switching among the 3 cords makes no difference.) This is independent of the camera or transmitter -- happens when it is not on the camera. (Haven't tried having my husband take it to work with him to get it out of range... guess I could take the battery out.) But this doesn't sound like any sort of transmitter glitch.

Have changed all batteries, and talked to MicroSync tech support. They said send it in to be checked out, which I did, and they sent a new replacement at no charge. I thought, OK, they found some problem. (It was out of warranty but not by a lot.) I hooked up the new receiver and it did the same thing!

I only have one battery pack so can't test it. Just wondering if anyone else has seen this? (Eneloop batteries, if that matters.)