Components jumping off the board

Hello,

Recently I have change our profiles. After I profile one board it look really good, within the paste spec. But I have noticed when board leaves the reflow zone and enters the cooling zone it looks like popcorn effect some components jumping off the board and you can hear popping sound. I have adjusted the profile, it still looks ok but solderability doesn't look as good as before. Any idead why this popping occured?

Thank you

Marcin

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