How to play multiple rtmp streams at the same time on iOS?

Question

Objective-C

I am developing a client application whose task is to broadcast from the user to the server, and receive one video and three audio streams. The main difficulty is that the customer's server only sends rtmp . And if for iOS it was possible to find a solution for broadcasting video to the server, then there are problems with the simultaneous playback of "incoming" ones.
I currently only reproduce one with FFEngine.framework (great thing). Therefore, I ask the community for help, if there are any solutions in the form of libraries (paid or not - it doesn’t matter) that allow solving the task.