Connection drops after a few minutes

[Linschko 2]

I have that problem that I join a server with a good ping (around 51). Well, than everything goes normally but after a few minutes I ALWAYS loose connection on EVERY server :( I get that yellow chain. And why is it like that. I mean, I know that the Arma 2 engine sucks in every way, but I can play Planetside 2, or BF2 with WAY more people without any issues, This problem is going on for one week now, so what shall I do?