I do not know whether the direction I think in the right. There is one guess how to solve the problem with invisible players.
If I correctly understood the problem lies in the fact that the players on the channel may be only 30.
When connecting extra player (probably fail distribution system caused by the fact that many are included in the group of channels) ... Others can not perceive it.
I think that the problem can be solved by adding 4-6 reserved places on the channel, which will be sent extra players.