Pulse lenght mismatch

Hi,
<do_MessageReady> is signal, which pulses every time a message recieved from camera. It doesn't assigned to any device.
SocketReceive clientSocket\RawData:=raw_receive\Time:=WAIT_MAX;
PulseDO\High,do_MessageReady;
Sometimes, I see that this signal can last longer than the default 0.2s. What could be the reason?

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