There is a bug that could result in out-of-order events to be generated. Basically, Ringing or Connected even can be delayed waiting for the RTPproxy answer, while Disconnect event comes in in the meantime. As a result, such mis-ordering confuses CallController, which generates wrong accounting. Instead, check sequence numbers to all CCEvents and drop out-of-order events. This should resolve this and similar issues.
There is a bug that could result in out-of-order events to be generated.
Basically, Ringing or Connected even can be delayed waiting for the
RTPproxy answer, while Disconnect event comes in in the meantime.
As a result, such mis-ordering confuses CallController, which generates
wrong accounting. Instead, check sequence numbers to all CCEvents and
drop out-of-order events. This should resolve this and similar issues.

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