Wave stops being updated in real time after some activity

After launching a wave server (intranet) and testing it for a few minutes (deleting, writting, replying, etc..) it stops updating open waves in real time. This real time update problem remains until the server is restarted. It happens every single time after a couple of minutes of testing.

Interesting thing about it is that when person A writes something into a wave, all participants see the activity notification in real time (ajax) on the left side of the screen (it changes without reloading), but wave (opened one) itself does not show any changes unless whole page is reloaded.

When server is restarted, everything works well at the very beginning.