Teams Breakout Rooms Problems

HI, 

wondered if anyone can help. I find that when I create breakout rooms for 150 people on a teams call there always seems to be issues with people not being able to join, getting kicked out etc. The system gets very slow and isnt a nice participant experience. has anyone had this before and know of any tools that can help? I know Teams has a max number of 300 people for a breakout room event but even with half of that we have issues..