8620 totally has 16 MPSP boards and 1 MPCP board, convene two multi frame conferences. Two conferences are normal when having conferences with 8 frames. But when one of the conferences having 9 frames, system emerges conferences convene fail. One MPCP board should can process two multi frame conferences at most, and each channel can unite 16 frames. So, 16 MPSP boards can totally handle 32 frames. There should be no problem having two 16 frame conferences.
Operating 9 frames conference fail
Add one MPCP board on multi image frame without MPCP board. Notice: the redundant MPSP board is not useless, it is for realizing the TV wall
In fact, each multi image frame can have 8 MPSP boards and 2 MPCP boards. It means that one of the multi image frames doesn’t have MPCP board in this 8620. And just because this multi frame doesn’t have MPCP board causing this frame’s 8 MPSP board can’t use in multi frame function. So there are only 8 MPSP boards working and 16 channels image is being processed. That is why the 17th conference can’t join.