Garageband On iPad 1 Jam Session With Garageband on iPad 3 (Doesn't Work)

[leveck]

I have an iPad 1 running iOS 5.1.1 and an iPad 3 running iOS 7.1. Both are running the version of Garageband appropriate to the os version. They do not see a Jam Session started on the other device - so one started on the iPad 1 does not show on the iPad 3 and vice/versa. Are these two versions of Garageband incompatible, or do I have other issues with the iPad 1? I can see a session on the iPad 3 from my iOS 7 iPhone (both directions, starting and joining), is why I am implicating the iPad 1...